t/zbd: add -s option to test-zbd-support script

t/zbd: add -s option to test-zbd-support script

The total number of ZBD tests in test-zbd-support script has grown
considerably over the years and zoned drive capacity has significantly
increased as well. Today, the test run duration may reach one hour for
large drives. If a terminal session failure happens during a run, it
is more efficient to restart the tests from the point where the last
run stopped rather than from the beginning.

Add -s option to the script command line to specify the starting
test number.

Signed-off-by: Dmitry Fomichev <dmitry.fomichev@wdc.com>
Reviewed-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Link: https://lore.kernel.org/r/20240206105755.214891-6-dmitry.fomichev@wdc.com
Signed-off-by: Vincent Fu <vincent.fu@samsung.com>