Use the correct internal API for updating the battery level for PS5 controllers

src/joystick/hidapi/SDL_hidapi_ps5.c

@@ -798,18 +798,18 @@ HIDAPI_DriverPS5_HandleStatePacket(SDL_Joystick *joystick, hid_device *dev, SDL_
 
     if (packet->ucBatteryLevel & 0x10) {
         /* 0x20 set means fully charged */
-        joystick->epowerlevel = SDL_JOYSTICK_POWER_WIRED;
+        SDL_PrivateJoystickBatteryLevel(joystick, SDL_JOYSTICK_POWER_WIRED);
     } else {
         /* Battery level ranges from 0 to 10 */
         int level = (packet->ucBatteryLevel & 0xF);
         if (level == 0) {
-            joystick->epowerlevel = SDL_JOYSTICK_POWER_EMPTY;
+            SDL_PrivateJoystickBatteryLevel(joystick, SDL_JOYSTICK_POWER_EMPTY);
         } else if (level <= 2) {
-            joystick->epowerlevel = SDL_JOYSTICK_POWER_LOW;
+            SDL_PrivateJoystickBatteryLevel(joystick, SDL_JOYSTICK_POWER_LOW);
         } else if (level <= 7) {
-            joystick->epowerlevel = SDL_JOYSTICK_POWER_MEDIUM;
+            SDL_PrivateJoystickBatteryLevel(joystick, SDL_JOYSTICK_POWER_MEDIUM);
         } else {
-            joystick->epowerlevel = SDL_JOYSTICK_POWER_FULL;
+            SDL_PrivateJoystickBatteryLevel(joystick, SDL_JOYSTICK_POWER_FULL);
         }
     }