qla2xxx: Avoid escalating the SCSI error handler if the command is not found in firmware.

If the firmware cannot find the command specified then return SUCCESS to the
error handler so as not to needlessly escalate.  Also cleanup the resources for
the command since we cannot expect the original command to returned in
interrupt context.

Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@qlogic.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>