mediatek: mt7981: move gpio-controller up and rename pinctrl to pio

Move gpio-controller up to pinctrl node and rename label to "pio" to
match the label used in upstream kernel linux.

Update any DTS that reference the pinctrl to follow the new naming and
structure.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
diff --git a/arch/arm/dts/mt7981-rfb.dts b/arch/arm/dts/mt7981-rfb.dts
index d6ebd65..08e1b76 100644
--- a/arch/arm/dts/mt7981-rfb.dts
+++ b/arch/arm/dts/mt7981-rfb.dts
@@ -39,7 +39,7 @@
 	mediatek,gmac-id = <0>;
 	phy-mode = "2500base-x";
 	mediatek,switch = "mt7531";
-	reset-gpios = <&gpio 39 GPIO_ACTIVE_HIGH>;
+	reset-gpios = <&pio 39 GPIO_ACTIVE_HIGH>;
 
 	fixed-link {
 		speed = <2500>;
@@ -47,7 +47,7 @@
 	};
 };
 
-&pinctrl {
+&pio {
 	spi_flash_pins: spi0-pins-func-1 {
 		mux {
 			function = "flash";