Remove unused variables along with the related warnings.

Originally committed as revision 18413 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ptx.c

@@ -38,7 +38,6 @@ static av_cold int ptx_init(AVCodecContext *avctx) {
 static int ptx_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
                             AVPacket *avpkt) {
     const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
     PTXContext * const s = avctx->priv_data;
     AVFrame *picture = data;
     AVFrame * const p = &s->picture;

libavcodec/sunrast.c

@@ -45,7 +45,6 @@ static av_cold int sunrast_init(AVCodecContext *avctx) {
 static int sunrast_decode_frame(AVCodecContext *avctx, void *data,
                                 int *data_size, AVPacket *avpkt) {
     const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
     SUNRASTContext * const s = avctx->priv_data;
     AVFrame *picture = data;
     AVFrame * const p = &s->picture;

libavcodec/txd.c

@@ -41,7 +41,6 @@ static av_cold int txd_init(AVCodecContext *avctx) {
 static int txd_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
                             AVPacket *avpkt) {
     const uint8_t *buf = avpkt->data;
-    int buf_size = avpkt->size;
     TXDContext * const s = avctx->priv_data;
     AVFrame *picture = data;
     AVFrame * const p = &s->picture;