avcodec/h264_slice: Also check sei_recovery_frame_cnt for skip_frame nokey

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/h264_slice.c

@@ -1217,7 +1217,7 @@ int ff_h264_decode_slice_header(H264Context *h, H264SliceContext *sl)
             (h->avctx->skip_frame >= AVDISCARD_NONREF && !h->nal_ref_idc) ||
             (h->avctx->skip_frame >= AVDISCARD_BIDIR  && sl->slice_type_nos == AV_PICTURE_TYPE_B) ||
             (h->avctx->skip_frame >= AVDISCARD_NONINTRA && sl->slice_type_nos != AV_PICTURE_TYPE_I) ||
-            (h->avctx->skip_frame >= AVDISCARD_NONKEY && h->nal_unit_type != NAL_IDR_SLICE) ||
+            (h->avctx->skip_frame >= AVDISCARD_NONKEY && h->nal_unit_type != NAL_IDR_SLICE && h->sei_recovery_frame_cnt < 0) ||
             h->avctx->skip_frame >= AVDISCARD_ALL) {
             return SLICE_SKIPED;
         }