git-shell: Add 'git-upload-archive' to allowed commands.

This allows for example gitosis to allow use of 'git archive --remote' in a
controlled environment.

Signed-off-by: Erik Broes <erikbroes@ripe.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

shell.c

@@ -40,6 +40,7 @@ static struct commands {
 } cmd_list[] = {
 	{ "git-receive-pack", do_generic_cmd },
 	{ "git-upload-pack", do_generic_cmd },
+	{ "git-upload-archive", do_generic_cmd },
 	{ "cvs", do_cvs_cmd },
 	{ NULL },
 };