Fix typo.

git-svn-id: file:///var/local/repositories/ffmpeg/trunk@22988 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavutil/log.h

@@ -51,7 +51,7 @@ typedef struct {
 
     /**
      * LIBAVUTIL_VERSION with which this structure was created.
-     * This is used to allow fields to be added without requireing major
+     * This is used to allow fields to be added without requiring major
      * version bumps everywhere.
      */