doc/general: mention DST decoder

Signed-off-by: Paul B Mahol <onemda@gmail.com>

doc/general.texi

@@ -968,6 +968,7 @@ following image formats are supported:
 @item DSD (Direct Stream Digitial), least significant bit first, planar  @tab  @tab  X
 @item DSD (Direct Stream Digitial), most significant bit first, planar   @tab  @tab  X
 @item DSP Group TrueSpeech   @tab     @tab  X
+@item DST (Direct Stream Transfer) @tab  @tab  X
 @item DV audio               @tab     @tab  X
 @item Enhanced AC-3          @tab  X  @tab  X
 @item EVRC (Enhanced Variable Rate Codec) @tab     @tab  X