scsi: qla4xxx: remove two unused MSI-X related #defines

Spotted while preparing qla2xxx changes as the symbols exist in both
drivers (sigh..).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>