btrfs-progs: docs: btrfstune: sort options alphabetically

Signed-off-by: David Sterba <dsterba@suse.com>

Documentation/btrfstune.asciidoc

@@ -25,26 +25,10 @@ means.  Please refer to the 'FILESYSTEM FEATURES' in `btrfs`(5).
 
 OPTIONS
 -------
--S <0|1>::
-Enable seeding on a given device. Value 1 will enable seeding, 0 will disable it. +
-A seeding filesystem is forced to be mounted read-only. A new device can be added
-to the filesystem and will capture all writes keeping the seeding device intact.
 
--r::
+-f::
-(since kernel: 3.7)
+Allow dangerous changes, e.g. clear the seeding flag or change fsid. Make sure
-+
+that you are aware of the dangers.
-Enable extended inode refs (hardlink limit per file in a directory is 65536),
-enabled by mkfs feature 'extref'.
-
--x::
-(since kernel: 3.10)
-+
-Enable skinny metadata extent refs (more efficient representation of extents),
-enabled by mkfs feature 'skinny-metadata'.
-+
-All newly created extents will use the new representation. To completely switch
-the entire filesystem, run a full balance of the metadata. Please refer to
-`btrfs-balance`(8).
 
 -n::
 (since kernel: 3.14)
@@ -52,9 +36,24 @@ the entire filesystem, run a full balance of the metadata. Please refer to
 Enable no-holes feature (more efficient representation of file holes), enabled
 by mkfs feature 'no-holes'.
 
--f::
+-r::
-Allow dangerous changes, e.g. clear the seeding flag or change fsid. Make sure
+(since kernel: 3.7)
-that you are aware of the dangers.
++
+Enable extended inode refs (hardlink limit per file in a directory is 65536),
+enabled by mkfs feature 'extref'.
+
+-S <0|1>::
+Enable seeding on a given device. Value 1 will enable seeding, 0 will disable it. +
+A seeding filesystem is forced to be mounted read-only. A new device can be added
+to the filesystem and will capture all writes keeping the seeding device intact.
++
+WARNING: Clearing the seeding flag on a device may be dangerous.
+If a previously-seeding device is changed, all filesystems that used that
+device will become unmountable. Setting the seeding flag back will not fix
+that. +
+A valid usecase is 'seeding device as a base image'. Clear the seeding
+flag, update the filesystem and make it seeding again, provided that it's OK
+to throw away all filesystems built on top of the previous base.
 
 -u::
 Change fsid to a randomly generated UUID or continue previous fsid change
@@ -67,18 +66,20 @@ The 'UUID' should be a 36 bytes string in `printf`(3) format
 '"%08x-%04x-%04x-%04x-%012x"'.
 If there is a previous unfinished fsid change, it will continue only if the
 'UUID' matches the unfinished one or if you use the option '-u'.
-
++
 WARNING: Cancelling or interrupting a UUID change operation will make the
 filesystem temporarily unmountable.  To fix it, rerun 'btrfstune -u' to restore
 the UUID and let it complete.
 
-WARNING: Clearing the seeding flag on a device may be dangerous.
+-x::
-If a previously-seeding device is changed, all filesystems that used that
+(since kernel: 3.10)
-device will become unmountable. Setting the seeding flag back will not fix
++
-that. +
+Enable skinny metadata extent refs (more efficient representation of extents),
-A valid usecase is 'seeding device as a base image'. Clear the seeding
+enabled by mkfs feature 'skinny-metadata'.
-flag, update the filesystem and make it seeding again, provided that it's OK
++
-to throw away all filesystems built on top of the previous base.
+All newly created extents will use the new representation. To completely switch
+the entire filesystem, run a full balance of the metadata. Please refer to
+`btrfs-balance`(8).
 
 EXIT STATUS
 -----------