scsi: oak: Remove redundant initialization of variable ret

No point in initializing ret with -ENOMEM.

Link: https://lore.kernel.org/r/20200918090747.44645-1-jingxiangfeng@huawei.com


Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>