arm64: dts: rockchip: add an input enable pinconf to rk3399

Add a pinconf to configure pins as input-enable.
Signed-off-by: NCaleb Connolly <kc@postmarketos.org>
Link: https://lore.kernel.org/r/20220328005005.72492-5-kc@postmarketos.orgSigned-off-by: NHeiko Stuebner <heiko@sntech.de>

arch/arm64/boot/dts/rockchip/rk3399.dtsi

@@ -2211,6 +2211,22 @@
 			output-low;
 		};
 
+		pcfg_input_enable: pcfg-input-enable {
+			input-enable;
+		};
+
+		pcfg_input_pull_up: pcfg-input-pull-up {
+			input-enable;
+			bias-pull-up;
+			drive-strength = <2>;
+		};
+
+		pcfg_input_pull_down: pcfg-input-pull-down {
+			input-enable;
+			bias-pull-down;
+			drive-strength = <2>;
+		};
+
 		clock {
 			clk_32k: clk-32k {
 				rockchip,pins = <0 RK_PA0 2 &pcfg_pull_none>;