rev-parse: fix --verify to error out when passed junk after a good rev

rev-parse: fix --verify to error out when passed junk after a good rev

Before this patch something like:

$ git rev-parse --verify <good-rev> <junk>

worked whatever junk was as long as <good-rev> could be parsed
correctly.

This patch makes "git rev-parse --verify" error out when passed
any junk after a good rev.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>