Simplify t_sqrt()

Originally committed as revision 13918 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ra144.c

@@ -61,13 +61,13 @@ static int ra144_decode_init(AVCodecContext * avctx)
  */
 static int t_sqrt(unsigned int x)
 {
-    int s = 0;
+    int s = 2;
     while (x > 0xfff) {
         s++;
         x = x >> 2;
     }
 
-    return (ff_sqrt(x << 20) << s) << 2;
+    return ff_sqrt(x << 20) << s;
 }
 
 /**