mpt2sas: Fix for device scan following host reset could get stuck in a infinite loop

commit 6241f22ca12a26ee149cbe31b27bac97dbdc8bc4 upstream.

Modified device scan routine so each configuration page read breaks from the
while loop when the ioc_status is not equal to MPI2_IOCSTATUS_SUCCESS.

[jejb: checkpatch fixes]
Signed-off-by: Sreekanth Reddy <Sreekanth.Reddy@lsi.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
[bwh: Backported to 3.2; adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>