[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.