ass_split: fix invalid doxygen group end markers.

libavcodec/ass_split.h

@@ -130,7 +130,7 @@ typedef struct {
     void (*font_size)(void *priv, int size);
     void (*alignment)(void *priv, int alignment);
     void (*cancel_overrides)(void *priv, const char *style);
-    /**< @} */
+    /** @} */
 
     /**
      * @defgroup ass_functions    ASS functions
@@ -138,14 +138,14 @@ typedef struct {
      */
     void (*move)(void *priv, int x1, int y1, int x2, int y2, int t1, int t2);
     void (*origin)(void *priv, int x, int y);
-    /**< @} */
+    /** @} */
 
     /**
      * @defgroup ass_end    end of Dialogue Event
      * @{
      */
     void (*end)(void *priv);
-    /**< @} */
+    /** @} */
 } ASSCodesCallbacks;
 
 /**