arm64: dts: imx8ulp-evk: enable lpi2c7 bus

Enable lpi2c7 bus, and enable i2c IO expander.
Reviewed-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Haibo Chen <haibo.chen@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8ulp-evk.dts

@@ -118,6 +118,23 @@ &lpuart5 {
 	status = "okay";
 };
 
+&lpi2c7 {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	clock-frequency = <400000>;
+	pinctrl-names = "default", "sleep";
+	pinctrl-0 = <&pinctrl_lpi2c7>;
+	pinctrl-1 = <&pinctrl_lpi2c7>;
+	status = "okay";
+
+	pcal6408: gpio@21 {
+		compatible = "nxp,pcal9554b";
+		reg = <0x21>;
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
+};
+
 &usdhc0 {
 	pinctrl-names = "default", "state_100mhz", "state_200mhz", "sleep";
 	pinctrl-0 = <&pinctrl_usdhc0>;
@@ -200,6 +217,13 @@ MX8ULP_PAD_PTF15__LPUART5_RX	0x3
 		>;
 	};
 
+	pinctrl_lpi2c7: lpi2c7grp {
+		fsl,pins = <
+			MX8ULP_PAD_PTE12__LPI2C7_SCL	0x20
+			MX8ULP_PAD_PTE13__LPI2C7_SDA	0x20
+		>;
+	};
+
 	pinctrl_usdhc0: usdhc0grp {
 		fsl,pins = <
 			MX8ULP_PAD_PTD1__SDHC0_CMD	0x3