doc/general: sort subtitles formats.

doc/general.texi

@@ -918,7 +918,7 @@ performance on systems without hardware floating point support).
 
 @multitable @columnfractions .4 .1 .1 .1 .1
 @item Name @tab Muxing @tab Demuxing @tab Encoding @tab Decoding
-@item SSA/ASS          @tab X @tab X @tab X @tab X
+@item 3GPP Timed Text  @tab   @tab   @tab X @tab X
 @item DVB              @tab X @tab X @tab X @tab X
 @item DVD              @tab X @tab X @tab X @tab X
 @item JACOsub          @tab X @tab X @tab   @tab X
@@ -926,11 +926,11 @@ performance on systems without hardware floating point support).
 @item PGS              @tab   @tab   @tab   @tab X
 @item RealText         @tab   @tab X @tab   @tab X
 @item SAMI             @tab   @tab X @tab   @tab X
+@item SSA/ASS          @tab X @tab X @tab X @tab X
 @item SubRip (SRT)     @tab X @tab X @tab X @tab X
 @item SubViewer        @tab   @tab X @tab   @tab X
 @item TED Talks captions @tab @tab X @tab   @tab X
 @item VobSub (IDX+SUB) @tab   @tab X @tab   @tab X
-@item 3GPP Timed Text  @tab   @tab   @tab X @tab X
 @item WebVTT           @tab   @tab X @tab   @tab X
 @item XSUB             @tab   @tab   @tab X @tab X
 @end multitable