scsi: fusion: Fix error return code in mptfc_probe()

Fix to return error code -ENOMEM from the workqueue alloc error handling
case instead of 0, as done elsewhere in this function.

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>