pack: move pack-closing functions

The function close_pack_fd() needs to be temporarily made global. Its
scope will be restored to static in a subsequent commit.

Signed-off-by: Jonathan Tan <jonathantanmy@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/fetch.c

@@ -17,6 +17,7 @@
 #include "connected.h"
 #include "argv-array.h"
 #include "utf8.h"
+#include "packfile.h"
 
 static const char * const builtin_fetch_usage[] = {
 	N_("git fetch [<options>] [<repository> [<refspec>...]]"),