asf: dont warn the user about digital sigantures, they should on their own not cause failure.

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

libavformat/asfdec.c

@@ -642,7 +642,7 @@ static int asf_read_header(AVFormatContext *s, AVFormatParameters *ap)
                     av_log(s, AV_LOG_WARNING, "Ext DRM protected stream detected, decoding will likely fail!\n");
                     av_dict_set(&s->metadata, "encryption", "ASF Extended Content Encryption", 0);
                 } else if (!ff_guidcmp(&g, &ff_asf_digital_signature)) {
-                    av_log(s, AV_LOG_WARNING, "Digital signature detected, decoding will likely fail!\n");
+                    av_log(s, AV_LOG_INFO, "Digital signature detected!\n");
                 }
             }
         }