drivers: adc: stm32: use dedicated status function for ldo state

Now that the U5 HAL contains the dedicated LDO status function, use it
instead of reading the register directly.

Signed-off-by: Guillaume Gautier <[email protected]>

Author: gautierg-st

drivers/adc/adc_stm32.c

@@ -1623,10 +1623,7 @@ static int adc_stm32_init(const struct device *dev)
 #elif defined(CONFIG_SOC_SERIES_STM32H7X) || \
 	defined(CONFIG_SOC_SERIES_STM32U5X) || \
 	defined(CONFIG_SOC_SERIES_STM32WBAX)
-	/* Don't use LL_ADC_IsActiveFlag_LDORDY since not present in U5 LL (1.5.0)
-	 * (internal issue 185106)
-	 */
-	while ((READ_BIT(adc->ISR, LL_ADC_FLAG_LDORDY) != (LL_ADC_FLAG_LDORDY))) {
+	while (LL_ADC_IsActiveFlag_LDORDY(adc) == 0) {
 	}
 #else
 	k_busy_wait(LL_ADC_DELAY_INTERNAL_REGUL_STAB_US);