[SCSI] megaraid_sas: Set IoFlags to enable Fast Path for JBODs for 12 Gb/s controllers

Signed-off-by: Sumit Saxena <sumit.saxena@lsi.com>
Signed-off-by: Kashyap Desai <kashyap.desai@lsi.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>