avutil/hwcontext: Add ohcodec device and pixel format

Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>

libavutil/pixdesc.c

@@ -3263,6 +3263,10 @@ static const AVPixFmtDescriptor av_pix_fmt_descriptors[AV_PIX_FMT_NB] = {
         },
         .flags = AV_PIX_FMT_FLAG_BE,
     },
+    [AV_PIX_FMT_OHCODEC] = {
+        .name = "ohcodec",
+        .flags = AV_PIX_FMT_FLAG_HWACCEL,
+    },
 };
 
 static const char * const color_range_names[] = {