scsi: lpfc: Remove unnecessary null check before kfree

A null check before a kfree is redundant, so remove it.  This is detected
by coccinelle.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>