doxygen: score: adjust doc in threadq.h to doxygen guidelines

Update #3706.

cpukit/include/rtems/score/threadq.h

@@ -1,6 +1,8 @@
 /**
  * @file
  *
+ * @ingroup RTEMSScoreThreadQueue
+ *
  * @brief Constants and Structures Needed to Declare a Thread Queue
  *
  * This include file contains all the constants and structures
@@ -40,11 +42,14 @@ struct Scheduler_Node;
  *
  * @ingroup RTEMSScore
  *
+ * @brief Thread Queue Handler
+ *
  * This handler provides the capability to have threads block in
  * ordered sets. The sets may be ordered using the FIFO or priority
  * discipline.
+ *
+ * @{
  */
-/**@{*/
 
 typedef struct _Thread_Control Thread_Control;