t/zbd: add an option to bail on a failed test

t/zbd: add an option to bail on a failed test

Sometimes, it can be useful to inspect the state of the zones of the
test device, usually right after a test failure. Currently,
test-zbd-support script just keeps running and proper examination of
device zones can be difficult.

Add the -q option to test/zbd/support to quit immediately upon
encountering any test failure. Additionally, define the same option
in run-tests-against-nullb to propagate it to test/zbd/support.

Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>