btrfs: sort error decoder entries

Add the raw errnos and sort them accordingly.
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/super.c

@@ -72,23 +72,23 @@ const char * __attribute_const__ btrfs_decode_error(int errno)
 	char *errstr = "unknown";
 
 	switch (errno) {
-	case -EIO:
+	case -ENOENT:		/* -2 */
+		errstr = "No such entry";
+		break;
+	case -EIO:		/* -5 */
 		errstr = "IO failure";
 		break;
-	case -ENOMEM:
+	case -ENOMEM:		/* -12*/
 		errstr = "Out of memory";
 		break;
-	case -EROFS:
-		errstr = "Readonly filesystem";
-		break;
-	case -EEXIST:
+	case -EEXIST:		/* -17 */
 		errstr = "Object already exists";
 		break;
-	case -ENOSPC:
+	case -ENOSPC:		/* -28 */
 		errstr = "No space left";
 		break;
-	case -ENOENT:
-		errstr = "No such entry";
+	case -EROFS:		/* -30 */
+		errstr = "Readonly filesystem";
 		break;
 	}