avcodec/cri: Make decoder init-threadsafe

The only thing that stands in the way of adding the
FF_CODEC_CAP_INIT_THREADSAFE flag to the Cintel RAW decoder is its usage
of ff_codec_open2_recursive(): This function requires its caller to hold
the lock for the mutex that guards initialization of AVCodecContexts
whose codecs have a non-threadsafe init function and only callers whose
codec does not have the FF_CODEC_CAP_INIT_THREADSAFE flag set hold said
lock (the others don't need to care about said lock). But one can set
the flag if one switches to avcodec_open2() at the same time.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>

libavcodec/cri.c

@@ -66,7 +66,7 @@ static av_cold int cri_decode_init(AVCodecContext *avctx)
     s->jpeg_avctx->flags2 = avctx->flags2;
     s->jpeg_avctx->dct_algo = avctx->dct_algo;
     s->jpeg_avctx->idct_algo = avctx->idct_algo;
-    ret = ff_codec_open2_recursive(s->jpeg_avctx, codec, NULL);
+    ret = avcodec_open2(s->jpeg_avctx, codec, NULL);
     if (ret < 0)
         return ret;
 
@@ -419,6 +419,6 @@ AVCodec ff_cri_decoder = {
     .decode         = cri_decode_frame,
     .close          = cri_decode_close,
     .capabilities   = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
-    .caps_internal  = FF_CODEC_CAP_INIT_CLEANUP,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
     .long_name      = NULL_IF_CONFIG_SMALL("Cintel RAW"),
 };