git-gui: sort entries in tclIndex

ALL_LIBFILES uses wildcard, which provides the result in directory
order. This order depends on the underlying filesystem on the
buildhost. To get reproducible builds it is required to sort such list
before using them.

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>

Author: olafhering

Makefile

@@ -259,7 +259,7 @@ lib/tclIndex: $(ALL_LIBFILES) GIT-GUI-VARS
 	 rm -f $@ ; \
 	 echo '# Autogenerated by git-gui Makefile' >$@ && \
 	 echo >>$@ && \
-	 $(foreach p,$(PRELOAD_FILES) $(ALL_LIBFILES),echo '$(subst lib/,,$p)' >>$@ &&) \
+	 $(foreach p,$(PRELOAD_FILES) $(sort $(ALL_LIBFILES)),echo '$(subst lib/,,$p)' >>$@ &&) \
 	 echo >>$@ ; \
 	fi