Introduce lpfc_prep_wqe routine.

The lpfc_prep_wqe() routine is used with lpfc_sli_issue_iocb() and
lpfc_sli_issue_iocb_wait(). The routine performs additional SLI-4 wqe field
setting that the generic routines did not perform as they kept their
actions compatible with both SLI3 and SLI4.

Link: https://lore.kernel.org/r/20220225022308.16486-4-jsmart2021@gmail.comCo-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>