block/004: Provide max_active_zones to fio command

block/004: Provide max_active_zones to fio command

If the test target devices is a zoned block device with max_active_zones
limit, the fio command in block/004 opens zones beyond the limit and
fails with I/O errors.

To avoid the failure, pass the limit value to fio using --max_open_zones
option. This option, which was introduced to fio together with
zonemode=zbd, keeps the number of open zones within the specified value.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>