mfd: mt6397: IRQ domain should initialize before mfd_add_devices()

Some sub driver like RTC module need irq domain from parent to create
irq mapping when driver initialize. so move mt6397_irq_init() before
mfd_add_devices().

Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Henry Chen <henryc.chen@mediatek.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/mt6397-core.c b/drivers/mfd/mt6397-core.c
index 5a3ffa3..e14d8b0 100644
--- a/drivers/mfd/mt6397-core.c
+++ b/drivers/mfd/mt6397-core.c
@@ -267,15 +267,23 @@
 	ret = regmap_read(pmic->regmap, MT6397_CID, &id);
 	if (ret) {
 		dev_err(pmic->dev, "Failed to read chip id: %d\n", ret);
-		goto fail_irq;
+		return ret;
 	}
 
+	pmic->irq = platform_get_irq(pdev, 0);
+	if (pmic->irq <= 0)
+		return pmic->irq;
+
 	switch (id & 0xff) {
 	case MT6323_CID_CODE:
 		pmic->int_con[0] = MT6323_INT_CON0;
 		pmic->int_con[1] = MT6323_INT_CON1;
 		pmic->int_status[0] = MT6323_INT_STATUS0;
 		pmic->int_status[1] = MT6323_INT_STATUS1;
+		ret = mt6397_irq_init(pmic);
+		if (ret)
+			return ret;
+
 		ret = devm_mfd_add_devices(&pdev->dev, -1, mt6323_devs,
 					   ARRAY_SIZE(mt6323_devs), NULL,
 					   0, NULL);
@@ -287,6 +295,10 @@
 		pmic->int_con[1] = MT6397_INT_CON1;
 		pmic->int_status[0] = MT6397_INT_STATUS0;
 		pmic->int_status[1] = MT6397_INT_STATUS1;
+		ret = mt6397_irq_init(pmic);
+		if (ret)
+			return ret;
+
 		ret = devm_mfd_add_devices(&pdev->dev, -1, mt6397_devs,
 					   ARRAY_SIZE(mt6397_devs), NULL,
 					   0, NULL);
@@ -298,14 +310,6 @@
 		break;
 	}
 
-	pmic->irq = platform_get_irq(pdev, 0);
-	if (pmic->irq > 0) {
-		ret = mt6397_irq_init(pmic);
-		if (ret)
-			return ret;
-	}
-
-fail_irq:
 	if (ret) {
 		irq_domain_remove(pmic->irq_domain);
 		dev_err(&pdev->dev, "failed to add child devices: %d\n", ret);