clock_control: clock_stm32_ll_mp2: add wwdg1 clock support

WWDG1 clock = ((MCU clock / LSMCU div) /APB3 prescaler)

Signed-off-by: Luc BEAUFILS <luc.beaufils@savoirfairelinux.com>

Author: lucbeaufils

drivers/clock_control/clock_stm32_ll_mp2.c

@@ -86,6 +86,10 @@ static int stm32_clock_control_get_subsys_rate(const struct device *dev,
 		break;
 	case STM32_CLOCK_PERIPH_I2C7:
 		*rate = LL_RCC_GetI2CClockFreq(LL_RCC_I2C7_CLKSOURCE);
+	case STM32_CLOCK_PERIPH_WWDG1:
+		/* The WWDG1 clock is derived from the APB3 clock */
+		int clock = 400000000 >> LL_RCC_Get_LSMCUDIVR();
+		*rate = clock >> LL_RCC_GetAPB3Prescaler();
 		break;
 	default:
 		return -ENOTSUP;