drivers: adc: rts5912: clear pending irq when setup

clear pending irq when setup.

Signed-off-by: jhan bo chao <jhan_bo_chao@realtek.com>

Author: JhanBoChao-Realtek

drivers/adc/adc_realtek_rts5912.c

@@ -260,6 +260,7 @@ static int adc_rts5912_init(const struct device *dev)
 
 	regs->ctrl = ADC_CTRL_RST;
 
+	NVIC_ClearPendingIRQ(DT_INST_IRQN(0));
 	IRQ_CONNECT(DT_INST_IRQN(0), DT_INST_IRQ(0, priority), adc_rts5912_single_isr,
 		    DEVICE_DT_INST_GET(0), 0);
 	irq_enable(DT_INST_IRQN(0));