Use $(MKDIR_P) instead of @MKDIR_P@

[Simon Josefsson]

Getting gnulib to build natively on Windows was a bit difficult, "make"
appears to break when trying to CreateProcess on /usr/bin/mkdir which
doesn't exist as a binary.  How about this patch?  It allows users to
specify the mkdir command when invoking 'make'.

The patch seems generally to be the Right Thing, but maybe there are
other ways to handle the missing mkdir issue on Windows?

/Simon

diff --git a/modules/arpa_inet b/modules/arpa_inet
index 55aa68f..cee421b 100644
--- a/modules/arpa_inet
+++ b/modules/arpa_inet
@@ -20,7 +20,7 @@ BUILT_SOURCES += $(ARPA_INET_H)
 # We need the following in order to create <arpa/inet.h> when the system
 # doesn't have one.
 arpa/inet.h: arpa_inet.in.h
-       $(AM_V_at)@MKDIR_P@ arpa
+       $(AM_V_at)$(MKDIR_P) arpa
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
diff --git a/modules/netinet_in b/modules/netinet_in
index 2c1a21a..54aab58 100644
--- a/modules/netinet_in
+++ b/modules/netinet_in
@@ -19,7 +19,7 @@ BUILT_SOURCES += $(NETINET_IN_H)
 # We need the following in order to create <netinet/in.h> when the system
 # doesn't have one.
 netinet/in.h: netinet_in.in.h
-       $(AM_V_at)@MKDIR_P@ netinet
+       $(AM_V_at)$(MKDIR_P) netinet
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
diff --git a/modules/sys_file b/modules/sys_file
index 8e155c8..9842380 100644
--- a/modules/sys_file
+++ b/modules/sys_file
@@ -19,7 +19,7 @@ BUILT_SOURCES += $(SYS_FILE_H)
 # We need the following in order to create <sys/file.h> when the system
 # has one that is incomplete.
 sys/file.h: sys_file.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's/@''HAVE_SYS_FILE_H''@/$(HAVE_SYS_FILE_H)/g' \
diff --git a/modules/sys_ioctl b/modules/sys_ioctl
index eb224f2..f6f3793 100644
--- a/modules/sys_ioctl
+++ b/modules/sys_ioctl
@@ -20,7 +20,7 @@ BUILT_SOURCES += $(SYS_IOCTL_H)
 # We need the following in order to create <sys/ioctl.h> when the system
 # does not have a complete one.
 sys/ioctl.h: sys_ioctl.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''HAVE_SYS_IOCTL_H''@|$(HAVE_SYS_IOCTL_H)|g' \
diff --git a/modules/sys_select b/modules/sys_select
index 2f6bdae..46296c0 100644
--- a/modules/sys_select
+++ b/modules/sys_select
@@ -21,7 +21,7 @@ BUILT_SOURCES += $(SYS_SELECT_H)
 # We need the following in order to create <sys/select.h> when the system
 # doesn't have one that works with the given compiler.
 sys/select.h: sys_select.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
diff --git a/modules/sys_socket b/modules/sys_socket
index e082f94..78c7df9 100644
--- a/modules/sys_socket
+++ b/modules/sys_socket
@@ -22,7 +22,7 @@ BUILT_SOURCES += $(SYS_SOCKET_H)
 # We need the following in order to create <sys/socket.h> when the system
 # doesn't have one that works with the given compiler.
 sys/socket.h: sys_socket.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
diff --git a/modules/sys_stat b/modules/sys_stat
index 60563c2..e4fba73 100644
--- a/modules/sys_stat
+++ b/modules/sys_stat
@@ -19,7 +19,7 @@ BUILT_SOURCES += $(SYS_STAT_H)
 # We need the following in order to create <sys/stat.h> when the system
 # has one that is incomplete.
 sys/stat.h: sys_stat.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \
diff --git a/modules/sys_time b/modules/sys_time
index 1e3953b..5355040 100644
--- a/modules/sys_time
+++ b/modules/sys_time
@@ -18,7 +18,7 @@ BUILT_SOURCES += $(SYS_TIME_H)
 # We need the following in order to create <sys/time.h> when the system
 # doesn't have one that works with the given compiler.
 sys/time.h: sys_time.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's/@''HAVE_SYS_TIME_H''@/$(HAVE_SYS_TIME_H)/g' \
diff --git a/modules/sys_times b/modules/sys_times
index 4cbaae5..3e4ead9 100644
--- a/modules/sys_times
+++ b/modules/sys_times
@@ -18,7 +18,7 @@ BUILT_SOURCES += $(SYS_TIMES_H)
 # We need the following in order to create <sys/times.h> when the system
 # doesn't have one that works with the given compiler.
 sys/times.h: sys_times.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''GNULIB_TIMES''@|$(GNULIB_TIMES)|g' \
diff --git a/modules/sys_utsname b/modules/sys_utsname
index 7ea102c..0ea9d89 100644
--- a/modules/sys_utsname
+++ b/modules/sys_utsname
@@ -18,7 +18,7 @@ BUILT_SOURCES += $(SYS_UTSNAME_H)
 # We need the following in order to create <sys/utsname.h> when the system
 # does not have one.
 sys/utsname.h: sys_utsname.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''GNULIB_UNAME''@|$(GNULIB_UNAME)|g' \
diff --git a/modules/sys_wait b/modules/sys_wait
index 7907e53..7e04c6e 100644
--- a/modules/sys_wait
+++ b/modules/sys_wait
@@ -19,7 +19,7 @@ BUILT_SOURCES += $(SYS_WAIT_H)
 # We need the following in order to create <sys/wait.h> when the system
 # has one that is incomplete.
 sys/wait.h: sys_wait.in.h
-       $(AM_V_at)@MKDIR_P@ sys
+       $(AM_V_at)$(MKDIR_P) sys
        $(AM_V_GEN)rm -f address@hidden $@ && \
        { echo '/* DO NOT EDIT! GENERATED AUTOMATICALLY! */'; \
          sed -e 's|@''INCLUDE_NEXT''@|$(INCLUDE_NEXT)|g' \