compilation.txt install

[Kevin Ryde]

In today's cvs, when doing a "make install" with srcdir!=builddir I
get a message about compilation.txt,

        Copying etc/DOC-* to /down/emacs/b/inst/share/emacs/21.3.50/etc ...
        DOC
        DOC-21.3.50.1
        DOC-21.3.50.2
        DOC-21.3.50.3
        tar: compilation.txt: Cannot stat: No such file or directory
        tar: Error exit delayed from previous errors

It looks like compilation.txt is not in $(builddir)/etc, only in the
normal $(srcdir)/etc.  It seems to get installed fine along with the
rest of the plain files in that directory though.