git-{fetch,peek-remote} handling of --upload-pack

git-peek-remote needs to handle a -u|--upload-pack parameter just like
git-fetch (and git-fetch has to pass it on to git-peek-remote).

(This is actually a follow-up to my previous git-fetch patch.)

Signed-off-by: Michal Ostrowski <mostrows@heater.watson.ibm.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>