This trivial patch makes "git-rev-list" able to handle not being in
the top-level directory.  This magically also makes "git-whatchanged"
do the right thing.

Trivial scripting fix to make sure that "git log" also works.
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
Signed-off-by: NJunio C Hamano <junkio@cox.net>