Proresenc: add multithreading support

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/proresenc_anatoliy.c

@@ -606,6 +606,7 @@ AVCodec ff_prores_anatoliy_encoder = {
     .encode2        = prores_encode_frame,
     .pix_fmts       = (const enum PixelFormat[]){PIX_FMT_YUV422P10, PIX_FMT_NONE},
     .long_name      = NULL_IF_CONFIG_SMALL("Apple ProRes"),
+    .capabilities   = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY,
     .profiles       = profiles
 };
 
@@ -619,5 +620,6 @@ AVCodec ff_prores_encoder = {
     .encode2        = prores_encode_frame,
     .pix_fmts       = (const enum PixelFormat[]){PIX_FMT_YUV422P10, PIX_FMT_NONE},
     .long_name      = NULL_IF_CONFIG_SMALL("Apple ProRes"),
+    .capabilities   = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY,
     .profiles       = profiles
 };