Fixed compilation with avcodec without MT support.

modules/codec/avcodec/video.c

@@ -349,11 +349,13 @@ int InitVideoDec( decoder_t *p_dec, AVCodecContext *p_context,
          i_codec_id == CODEC_ID_H264 ||
          i_codec_id == CODEC_ID_VC1 || i_codec_id == CODEC_ID_WMV3) )
     {
+#ifdef HAVE_AVCODEC_MT
         if( p_sys->p_context->thread_type & FF_THREAD_FRAME )
         {
             msg_Warn( p_dec, "threaded frame decoding is not compatible with ffmpeg-hw, disabled" );
             p_sys->p_context->thread_type &= ~FF_THREAD_FRAME;
         }
+#endif
         p_sys->p_context->get_format = ffmpeg_GetFormat;
     }
 #endif