mfd: stpmic1: Use devm_register_power_off_handler()

Simplify the code a bit by using devm_register_power_off_handler(), which is
a purpose-specific wrapper for devm_register_sys_off_handler(). No intended
functional changes are introduced.

Signed-off-by: Dragan Simic <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/stpmic1.c

···
 		return ret;
 	}
 
-	ret = devm_register_sys_off_handler(ddata->dev,
-					    SYS_OFF_MODE_POWER_OFF,
-					    SYS_OFF_PRIO_DEFAULT,
-					    stpmic1_power_off,
-					    ddata);
+	ret = devm_register_power_off_handler(ddata->dev, stpmic1_power_off, ddata);
 	if (ret) {
 		dev_err(ddata->dev, "failed to register sys-off handler: %d\n", ret);
 		return ret;