Makefile: add missing dependency on http.h

v1.7.1-rc0~65^2~2 (http: init and cleanup separately from
http-walker, 2010-03-02) introduced a direct dependency from
http-fetch on the HTTP request library.  Declare it.

Detected with "make CHECK_HEADER_DEPENDENCIES=1".

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by: Tay Ray Chuan <rctay89@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -1856,7 +1856,7 @@ builtin/tar-tree.o archive-tar.o: tar.h
 builtin/pack-objects.o: thread-utils.h
 connect.o transport.o http-backend.o: url.h
 http-fetch.o http-walker.o remote-curl.o transport.o walker.o: walker.h
-http.o http-walker.o http-push.o remote-curl.o: http.h
+http.o http-walker.o http-push.o http-fetch.o remote-curl.o: http.h
 
 xdiff-interface.o $(XDIFF_OBJS): \
 	xdiff/xinclude.h xdiff/xmacros.h xdiff/xdiff.h xdiff/xtypes.h \