cosmetics: typo

Originally committed as revision 13443 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/ra144.c

@@ -57,7 +57,7 @@ static int ra144_decode_init(AVCodecContext * avctx)
 }
 
 /**
- * Evaluate sqrt(x << 24). x must fit in 20 bits. This value is evaluated in a
+ * Evaluate sqrt(x << 24). x must fit in 20 bits. This value is evaluated in an
  * odd way to make the output identical to the binary decoder.
  */
 static int t_sqrt(unsigned int x)