We have several exits from the function, each of which has
to do some cleanup. Let's consolidate these in an "out"
label we can jump to. This doesn't save us much now, but it
will help as we add more things that need cleanup.
Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>