[Docs] update suspend_*_user examples (#14542)

docs/custom_quantum_functions.md

@@ -214,11 +214,11 @@ This is controlled by two functions: `suspend_power_down_*` and `suspend_wakeup_
 
 ```c
 void suspend_power_down_user(void) {
-    rgb_matrix_set_suspend_state(true);
+    // code will run multiple times while keyboard is suspended
 }
 
 void suspend_wakeup_init_user(void) {
-    rgb_matrix_set_suspend_state(false);
+    // code will run on keyboard wakeup
 }
 ```
 

docs/ja/custom_quantum_functions.md

@@ -211,11 +211,11 @@ void keyboard_post_init_user(void) {
 
 ```c
 void suspend_power_down_user(void) {
-    rgb_matrix_set_suspend_state(true);
+    // code will run multiple times while keyboard is suspended
 }
 
 void suspend_wakeup_init_user(void) {
-    rgb_matrix_set_suspend_state(false);
+    // code will run on keyboard wakeup
 }
 ```
 

docs/zh-cn/custom_quantum_functions.md

@@ -275,11 +275,11 @@ void keyboard_post_init_user(void) {
 
 ```c
 void suspend_power_down_user(void) {
-    rgb_matrix_set_suspend_state(true);
+    // code will run multiple times while keyboard is suspended
 }
 
 void suspend_wakeup_init_user(void) {
-    rgb_matrix_set_suspend_state(false);
+    // code will run on keyboard wakeup
 }
 ```