scsi: lpfc: Fix loop mode target discovery

The driver does not discover targets when in loop mode.

The NLP type is correctly getting set when a fabric connection is
detected but, not for loop. The unknown NLP type means that the driver
does not issue a PRLI when in loop topology. Thus target discovery
fails.

Fix by checking the topology during discovery.  If it is loop, set the
NLP FC4 type to FCP.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>