scsi: fix comment in struct Scsi_Host definition

Commit 1abf635d (scsi: use 64-bit value for 'max_luns') changed the order
of Scsi_Host members. Update the comment to reflect this.
Signed-off-by: Sebastian Herbszt <herbszt@gmx.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

include/scsi/scsi_host.h

@@ -606,7 +606,7 @@ struct Scsi_Host {
 	/*
 	 * These three parameters can be used to allow for wide scsi,
 	 * and for host adapters that support multiple busses
-	 * The first two should be set to 1 more than the actual max id
+	 * The last two should be set to 1 more than the actual max id
 	 * or lun (e.g. 8 for SCSI parallel systems).
 	 */
 	unsigned int max_channel;