[SCSI] megaraid_mbox: fix Dell CERC firmware problem

Newer Dell CERC firmware (>= 6.62) implement a random deletion handling
compatible with the legacy megaraid driver.  The legacy handling shifted
the target ID by 0x80 only for I/O commands (READ/WRITE/etc), whereas
megaraid_mbox shifts the target ID always if random deletion is supported.
The resulted in megaraid_mbox sending an INQUIRY to the wrong channel, and
not finding any devices, obviously.

So we disable the random deletion support if the offending firmware is
found.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=6695

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Yang, Bo" <Bo.Yang@lsi.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>