scsi: lpfc: Reinstate lpfc_soft_wwn parameter

The lpfc 11.2.0.4 patch set deprecated, by removing, the lpfc_soft_wwn
parameter support.

This patch reinstates support, but adds a warning in the enablement of
the feature that indicates Broadcom (Emulex) does not support the
feature.

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