[SCSI] aacraid: General driver cleanup

Received from Mark Salyzyn

Remove superfluous code, optimize code, harden code, cast code, correct
some text, use msleep instead of schedule_timeout_interruptible. No
bugs.

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