megaraid_sas: MFI adapter OCR changes

megaraid_sas: MFI adapter OCR changes

BugLink: http://bugs.launchpad.net/bugs/1544679
Optimized MFI adapters' OCR path, particularly
megasas_wait_for_outstanding() function.

Signed-off-by: Kashyap Desai <kashyap.desai@avagotech.com>
Signed-off-by: Sumit Saxena <sumit.saxena@avagotech.com>
Reviewed-by: Tomas Henzl <thenzl@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from linux-next commit c05c7e5c091a6527bed7f31e0238749c845a4744)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>