http-push.c: rearrange xcalloc arguments

xcalloc() takes two arguments: the number of elements and their size.
http-push passes the arguments in reverse order, passing the size
of a repo, followed by the number to allocate.

Rearrange them so they are in the correct order.

Signed-off-by: Brian Gesiak <modocache@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

http-push.c

@@ -1732,7 +1732,7 @@ int main(int argc, char **argv)
 
 	git_extract_argv0_path(argv[0]);
 
-	repo = xcalloc(sizeof(*repo), 1);
+	repo = xcalloc(1, sizeof(*repo));
 
 	argv++;
 	for (i = 1; i < argc; i++, argv++) {