Doxygen comment update and PREDEFINED in Doxyfile is properly defined (#5186)

JerryScript-DCO-1.0-Signed-off-by: Yonggang Luo luoyonggang@gmail.com

jerry-core/ecma/base/ecma-gc.c

@@ -128,8 +128,6 @@ ecma_init_gc_info (ecma_object_t *object_p) /**< object */
 
 /**
  * Increase reference counter of an object
- *
- * @return void
  */
 extern inline void JERRY_ATTR_ALWAYS_INLINE
 ecma_ref_object_inline (ecma_object_t *object_p) /**< object */
@@ -155,8 +153,6 @@ ecma_ref_object (ecma_object_t *object_p) /**< object */
 
 /**
  * Decrease reference counter of an object
- *
- * @return void
  */
 extern inline void JERRY_ATTR_ALWAYS_INLINE
 ecma_deref_object (ecma_object_t *object_p) /**< object */
@@ -470,8 +466,6 @@ ecma_gc_mark_compiled_code (ecma_value_t script_value) /**< script value */
 
 /**
  * Mark objects referenced by bound function object.
- *
- * @return void
  */
 static void JERRY_ATTR_NOINLINE
 ecma_gc_mark_bound_function_object (ecma_object_t *object_p) /**< bound function object */