scsi: mpi3mr: Enable shared host tagset

Enable shared host tagset to make sure that total outstanding I/O count can
not exceed controller's can_queue setting.

Link: https://lore.kernel.org/r/20220628074848.5036-2-sreekanth.reddy@broadcom.com
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>