[SCSI] lpfc 8.3.8: (BSG4) Add new vendor specific BSG Commands

Add the following new vendor specific BSG commands.
- Add LPFC_BSG_VENDOR_GET_MGMT_REV command
- Add LPFC_BSG_VENDOR_MBOX command
- Add LPFC_BSG_VENDOR_DIAG_MODE command
- Add LPFC_BSG_VENDOR_DIAG_TEST command

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>