Makefile: Use 'git ls-files' instead of the deprecated 'git-ls-files' form.

Makefile.in

diff --git a/Makefile.in b/Makefile.in
index f2dbcfc..7ad6faa 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -141,11 +141,11 @@
 
 TAGS etags:
 	$(RM) TAGS
-	(test -d .git && git-ls-files '*.[chly]' '*.idl' || find -L $(TOPSRCDIR) -name '*.[ch]' -print) | xargs etags -a
+	(test -d .git && git ls-files '*.[chly]' '*.idl' || find -L $(TOPSRCDIR) -name '*.[ch]' -print) | xargs etags -a
 
 tags ctags:
 	$(RM) tags
-	(test -d .git && git-ls-files '*.[chly]' '*.idl' || find -L $(TOPSRCDIR) -name '*.[ch]' -print) | xargs ctags -a
+	(test -d .git && git ls-files '*.[chly]' '*.idl' || find -L $(TOPSRCDIR) -name '*.[ch]' -print) | xargs ctags -a
 
 manpages htmlpages sgmlpages: dummy
 	@cd documentation && $(MAKE) $@