ARM: dts: mmp3-dell-ariel: Replace SSP2 with spi-gpio

The firmware leaves the pins in GPIO mode. Until we have a proper pinmux
driver hooked on we just need to bitbang SPI. No big deal, this is just
used for the power button and performance is not important.
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20210121034130.1381872-12-lkundrak@v3.sk'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/boot/dts/mmp3-dell-ariel.dts

@@ -30,6 +30,17 @@ memory@0 {
 		reg = <0x0 0x80000000>;
 		device_type = "memory";
 	};
+
+	ec_input_spi: spi {
+		compatible = "spi-gpio";
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		num-chipselects = <0>;
+		sck-gpios = <&gpio 55 GPIO_ACTIVE_HIGH>;
+		miso-gpios = <&gpio 57 GPIO_ACTIVE_HIGH>;
+		mosi-gpios = <&gpio 58 GPIO_ACTIVE_HIGH>;
+	};
 };
 
 &uart3 {
@@ -118,7 +129,7 @@ firmware-flash@0 {
 	};
 };
 
-&ssp2 {
+&ec_input_spi {
 	status = "okay";
 	cs-gpios = <&gpio 56 GPIO_ACTIVE_LOW>;