Revert "general.texi: we dont have a g729 encoder yet"

This reverts commit 84f8aef40c.

doc/general.texi

@@ -107,7 +107,7 @@ library:
 @item FunCom ISS                @tab   @tab X
     @tab Audio format used in various games from FunCom like The Longest Journey.
 @item G.723.1                   @tab   @tab X
-@item G.729 BIT                 @tab   @tab X
+@item G.729 BIT                 @tab X @tab X
 @item GIF Animation             @tab X @tab
 @item GXF                       @tab X @tab X
     @tab General eXchange Format SMPTE 360M, used by Thomson Grass Valley