avcodec/bitpacked: Add codec_tags list

This should improve coverage
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavcodec/bitpacked.c

@@ -146,4 +146,8 @@ AVCodec ff_bitpacked_decoder = {
     .init = bitpacked_init_decoder,
     .decode = bitpacked_decode,
     .capabilities = AV_CODEC_CAP_EXPERIMENTAL,
+    .codec_tags     = (const uint32_t []){
+        MKTAG('U', 'Y', 'V', 'Y')
+        FF_CODEC_TAGS_END,
+    },
 };