scsi: lpfc: Rework sli4 doorbell infrastructure

Up until now, all SLI-4 devices had the same doorbells at the same
bar locations. With newer hardware, there are now independent EQ and
CQ doorbells and the bar locations differ.

Prepare the code for new hardware by separating the eq/cq doorbell into
separate components. The components can be set based on if_type.

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>