[PATCH] block/export/fuse.c: fix musl build

[Fabrice Fontaine]

Include linux/falloc.h if CONFIG_FALLOCATE_ZERO_RANGE is defined to fix
https://gitlab.com/qemu-project/qemu/-/commit/50482fda98bd62e072c30b7ea73c985c4e9d9bbb
and avoid the following build failure on musl:

../block/export/fuse.c: In function 'fuse_fallocate':
../block/export/fuse.c:643:21: error: 'FALLOC_FL_ZERO_RANGE' undeclared (first 
use in this function)
  643 |     else if (mode & FALLOC_FL_ZERO_RANGE) {
      |                     ^~~~~~~~~~~~~~~~~~~~

Fixes:
 - 
http://autobuild.buildroot.org/results/be24433a429fda681fb66698160132c1c99bc53b

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
---
 block/export/fuse.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/block/export/fuse.c b/block/export/fuse.c
index 2e3bf8270b..823c126d23 100644
--- a/block/export/fuse.c
+++ b/block/export/fuse.c
@@ -31,6 +31,10 @@
 #include <fuse.h>
 #include <fuse_lowlevel.h>
 
+#if defined(CONFIG_FALLOCATE_ZERO_RANGE)
+#include <linux/falloc.h>
+#endif
+
 #ifdef __linux__
 #include <linux/fs.h>
 #endif
-- 
2.33.0