assdec: don't remove CR, they are part of the spec

Originally committed as revision 15442 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/assdec.c

@@ -37,7 +37,7 @@ static void get_line(ByteIOContext *s, char *buf, int maxlen)
 
     do{
         c = get_byte(s);
-        if (i < maxlen-1 && c != '\r')
+        if (i < maxlen-1)
             buf[i++] = c;
     }while(c != '\n' && c);