[SCSI] aacraid: respond automatically to volumes added by config tool

Problem description:
--------------------

When the JBOD is created from the OS using Adaptec Storage Manager
utility device is not available under FDISK until a system restart is
done.

Solution:
---------

AIF handling: If there is a JBOD drive added to the system, identify
the old one with scsi_device_lookup() and remove it to enable a fresh
scsi_add_device(); else the new JBOD is not available until reboot.

Signed-off-by: Mahesh Rajashekhara <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>