mfd: max8997: Add of_compatible to Extcon and Charger mfd_cell

Add of_compatible ("maxim,max8997-muic") to the mfd_cell to have a
of_node set in the extcon driver.

Add of_compatible ("maxim,max8997-battery") to the mfd_cell to configure
the charger driver.
Signed-off-by: Timon Baetz <timon.baetz@protonmail.com>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/max8997.c

@@ -29,9 +29,9 @@
 static const struct mfd_cell max8997_devs[] = {
 	{ .name = "max8997-pmic", },
 	{ .name = "max8997-rtc", },
-	{ .name = "max8997-battery", },
+	{ .name = "max8997-battery", .of_compatible = "maxim,max8997-battery", },
 	{ .name = "max8997-haptic", },
-	{ .name = "max8997-muic", },
+	{ .name = "max8997-muic", .of_compatible = "maxim,max8997-muic", },
 	{ .name = "max8997-led", .id = 1 },
 	{ .name = "max8997-led", .id = 2 },
 };