[SCSI] qla2xxx: Correct needless clean-up resets during shutdown.

There's no point in hitting the RISC with what will most
assuredly be an unsucessful reset of the RISC hardware if the
initial stop-firmware mailbox command fails with a time-out
status.  Instead, to avoid what could amount to a lengthy
stop-firmware/detect-failure/reset-risc loop, continue with
driver unloading and discard the stop-firmware requirement.

Signed-off-by: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>