[doxygen] add doxygen comment for clk.c and clk.h

Accroding to #9947 and #9424, adding doxygen comment for function in .c files and data structure, macro in .h file is a solution.For this pr, I encountered problem following situations.
    - rt_clk_unprepare function return value type is different from rt_clk_ops so I change type of rt_clk_unprepare and its dependencies.
    - clk_get function may be similar as rt_clk_unprepare but I'm not sure so not modify.
    - clk_release implements may be incomplete, so I just marked in comment.

Signed-off-by: 1078249029 <[email protected]>

Author: 1078249029

components/drivers/clk/clk.c

@@ -454,13 +454,8 @@ static void clk_unprepare(struct rt_clk *clk, struct rt_clk_node *clk_np)
     }
 }
 
-/**
- * @brief   Unprepare clock
- *
- * @param   clk             point to clock
- *
- */
-void rt_clk_unprepare(struct rt_clk *clk)
+
+rt_err_t rt_clk_unprepare(struct rt_clk *clk)
 {
 
     RT_DEBUG_NOT_IN_INTERRUPT;

components/drivers/include/drivers/clk.h

@@ -160,7 +160,7 @@ rt_err_t rt_clk_notifier_unregister(struct rt_clk *clk, struct rt_clk_notifier *
 rt_err_t rt_clk_set_parent(struct rt_clk *clk, struct rt_clk *clk_parent);
 
 rt_err_t rt_clk_prepare(struct rt_clk *clk);
-void rt_clk_unprepare(struct rt_clk *clk);
+rt_err_t  rt_clk_unprepare(struct rt_clk *clk);
 
 rt_err_t rt_clk_enable(struct rt_clk *clk);
 void rt_clk_disable(struct rt_clk *clk);
@@ -169,7 +169,7 @@ rt_err_t rt_clk_prepare_enable(struct rt_clk *clk);
 void rt_clk_disable_unprepare(struct rt_clk *clk);
 
 rt_err_t rt_clk_array_prepare(struct rt_clk_array *clk_arr);
-void rt_clk_array_unprepare(struct rt_clk_array *clk_arr);
+rt_err_t  rt_clk_array_unprepare(struct rt_clk_array *clk_arr);
 
 rt_err_t rt_clk_array_enable(struct rt_clk_array *clk_arr);
 void rt_clk_array_disable(struct rt_clk_array *clk_arr);