Make networking commands to work from a subdirectory.

These are whole-tree operations and there is not much point
making them operable from within a subdirectory, but it is easy
to do so, and using setup_git_directory() upfront helps git://
proxy specification picked up from the correct place.

Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/ssh-fetch.c b/ssh-fetch.c
index bf01fbc..4eb9e04 100644
--- a/ssh-fetch.c
+++ b/ssh-fetch.c
@@ -131,6 +131,8 @@
 	prog = getenv("GIT_SSH_PUSH");
 	if (!prog) prog = "git-ssh-upload";
 
+	setup_git_directory();
+
 	while (arg < argc && argv[arg][0] == '-') {
 		if (argv[arg][1] == 't') {
 			get_tree = 1;