stream_filter/httplive.c: restore seeking

HTTP Live Streaming client does not support fast seeking, since that
would mean getting all data from the server. It would slowdown playback
of the stream until the end of the movie has been reached.

modules/stream_filter/httplive.c

@@ -2117,7 +2117,6 @@ static int Control(stream_t *s, int i_query, va_list args)
     switch (i_query)
     {
         case STREAM_CAN_SEEK:
-        case STREAM_CAN_FASTSEEK:
             *(va_arg (args, bool *)) = hls_MaySeek(s);
             break;
         case STREAM_GET_POSITION: