scsi: elx: libefc_sli: Populate and post different WQEs

Add service routines to create different WQEs and add APIs to issue iread,
iwrite, treceive, tsend and other work queue entries.

Link: https://lore.kernel.org/r/20210601235512.20104-6-jsmart2021@gmail.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Co-developed-by: Ram Vegesna <ram.vegesna@broadcom.com>
Signed-off-by: Ram Vegesna <ram.vegesna@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>