mfd: axp20x: Add AXP221/AXP223/AXP809 GPIO cells

These PMICs all contain a compatible GPIO controller.
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20220616060915.48325-3-samuel@sholland.org

drivers/mfd/axp20x.c

@@ -619,6 +619,9 @@ static const struct mfd_cell axp20x_cells[] = {
 
 static const struct mfd_cell axp221_cells[] = {
 	{
+		.name		= "axp20x-gpio",
+		.of_compatible	= "x-powers,axp221-gpio",
+	}, {
 		.name		= "axp221-pek",
 		.num_resources	= ARRAY_SIZE(axp22x_pek_resources),
 		.resources	= axp22x_pek_resources,
@@ -645,6 +648,9 @@ static const struct mfd_cell axp221_cells[] = {
 
 static const struct mfd_cell axp223_cells[] = {
 	{
+		.name		= "axp20x-gpio",
+		.of_compatible	= "x-powers,axp221-gpio",
+	}, {
 		.name		= "axp221-pek",
 		.num_resources	= ARRAY_SIZE(axp22x_pek_resources),
 		.resources	= axp22x_pek_resources,
@@ -785,6 +791,9 @@ static const struct mfd_cell axp806_cells[] = {
 
 static const struct mfd_cell axp809_cells[] = {
 	{
+		.name		= "axp20x-gpio",
+		.of_compatible	= "x-powers,axp221-gpio",
+	}, {
 		.name		= "axp221-pek",
 		.num_resources	= ARRAY_SIZE(axp809_pek_resources),
 		.resources	= axp809_pek_resources,