t6030 (bisect): work around Mac OS X "ls"
t6030 (bisect): work around Mac OS X "ls"

t6030-bisect-porcelain.sh relies on "ls" exiting with nonzero
status when asked to list nonexistent files.  Unfortunately,
/bin/ls on Mac OS X 10.3 exits with exit code 0.  So look at
its output instead.

Signed-off-by: Jonathan Nieder <b57189c5f2fd5b3daf3350a77fde90def1080fa5@uchicago.edu>
Acked-by: Christian Couder <ddbaab5867ed34fd53535b58c9cdd59abd2e2aff@tuxfamily.org>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git