[SCSI] aacraid: expose physical devices

[SCSI] aacraid: expose physical devices

Received from Mark Salyzyn:

I am placing this functionality into an insmod parameter. Normally the physical
components are exported to sg, and are blocked from showing up in sd.

Note that the pass-through I/O path via the driver through the Firmware to the
physical disks is not an optimized path, the card is designed for Hardware
RAID, elevator sorting and caching. This should not be used as a means for
utilizing the aacraid based controllers as a generic scsi/SATA/SAS controller,
performance should suck by a few percentage points, any RAID meta-data on the
drives will confuse the controller about who owns the drives and there is a
high risk of destroying content in both directions. Unreliable and for
experimentation or strange controlled circumstances only.

Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>