power: supply: wm831x: Check wm831x_set_bits() return value

Since wm831x_set_bits() may return error, log failure and exit from
wm831x_usb_limit_change() in such case.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 626b6cd ("power: wm831x_power: Support USB charger current limit management")
Signed-off-by: Ivan Abramov <i.abramov@mt-integration.ru>
Link: https://patch.msgid.link/20251009170553.566561-1-i.abramov@mt-integration.ru
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Author: Ivan Abramov

drivers/power/supply/wm831x_power.c

@@ -144,6 +144,7 @@ static int wm831x_usb_limit_change(struct notifier_block *nb,
 							 struct wm831x_power,
 							 usb_notify);
 	unsigned int i, best;
+	int ret;
 
 	/* Find the highest supported limit */
 	best = 0;
@@ -156,8 +157,13 @@ static int wm831x_usb_limit_change(struct notifier_block *nb,
 	dev_dbg(wm831x_power->wm831x->dev,
 		"Limiting USB current to %umA", wm831x_usb_limits[best]);
 
-	wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
-		        WM831X_USB_ILIM_MASK, best);
+	ret = wm831x_set_bits(wm831x_power->wm831x, WM831X_POWER_STATE,
+			      WM831X_USB_ILIM_MASK, best);
+	if (ret < 0) {
+		dev_err(wm831x_power->wm831x->dev,
+			"Failed to set USB current limit: %d\n", ret);
+		return ret;
+	}
 
 	return 0;
 }