Fix a doxygen comment

modules/demux/mkv.cpp

@@ -287,7 +287,7 @@ typedef struct {
  * values to use.  They are all represented by 4 bit number and stored
  * like this [Ci3, Ci2, Ci1, Ci0, A3, A2, A1, A0].   The actual palette
  * that the indexes reference is in the PGC.
- * @TODO split the uint32_t into a struct
+ * \todo split the uint32_t into a struct
  */
 typedef struct {
   uint32_t btn_coli[3][2];  /**< [button color number-1][select:0/action:1] */