scsi: lpfc: Add 256 Gb link speed support

Update routines to support 256 Gb link speed for LPe37000/LPe38000
adapters. 256 Gb speeds can be seen on trunk links.

Link: https://lore.kernel.org/r/20210722221721.74388-5-jsmart2021@gmail.com


Co-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>