[SCSI] aacraid: Add Power Management support

For firmware that supports the feature(s), add the ability to start or
stop an array using the associated SCSI commands, to automatically
manage the spin-up of an array on new I/O reporting back the
appropriate check conditions and actions in cooperation with the
normal timeout mechanisms and enable the blackout period management in
the Firmware associated with the background spin-down of the arrays
when the Firmware times out and deems the arrays as idle.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>