fetch.o depends on the headers, too.

Signed-off-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <junkio@cox.net>

Makefile

@@ -775,7 +775,7 @@ git-http-push$X: revision.o http.o http-push.o $(GITLIBS)
 	$(CC) $(ALL_CFLAGS) -o $@ $(ALL_LDFLAGS) $(filter %.o,$^) \
 		$(LIBS) $(CURL_LIBCURL) $(EXPAT_LIBEXPAT)
 
-$(LIB_OBJS) $(BUILTIN_OBJS): $(LIB_H)
+$(LIB_OBJS) $(BUILTIN_OBJS) fetch.o: $(LIB_H)
 $(patsubst git-%$X,%.o,$(PROGRAMS)): $(LIB_H) $(wildcard */*.h)
 $(DIFF_OBJS): diffcore.h