Add test_part_01.sh to test the UBLK_F_NO_AUTO_PART_SCAN feature
flag which allows suppressing automatic partition scanning during
device startup while still allowing manual partition probing.
The test verifies:
- Normal behavior: partitions are auto-detected without the flag
- With flag: partitions are not auto-detected during START_DEV
- Manual scan: blockdev --rereadpt works with the flag
Also update kublk tool to support --no_auto_part_scan option and
recognize the feature flag.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
