rtc: m41t80: Use the unified property API get the wakeup-source property

This allows both ACPI and Device Tree systems to specify the m41t80 as a
wakeup-source.

Signed-off-by: Curtis Klein <curtis.klein@hpe.com>
Link: https://lore.kernel.org/r/20240222011129.79241-1-curtis.klein@hpe.com
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

drivers/rtc/rtc-m41t80.c

@@ -909,10 +909,7 @@ static int m41t80_probe(struct i2c_client *client)
 	if (IS_ERR(m41t80_data->rtc))
 		return PTR_ERR(m41t80_data->rtc);
 
-#ifdef CONFIG_OF
-	wakeup_source = of_property_read_bool(client->dev.of_node,
-					      "wakeup-source");
-#endif
+	wakeup_source = device_property_read_bool(&client->dev, "wakeup-source");
 	if (client->irq > 0) {
 		unsigned long irqflags = IRQF_TRIGGER_LOW;