scsi: sd: Unlock zone in case of error in sd_setup_write_same_cmnd()

scsi_io_init() may fail, leaving a zone of a zoned block device locked.
Fix this by properly unlocking the write same request target zone if
scsi_io_init() fails.

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>