arm64: dts: k3-am654-base-board: Add I2C GPIO expander @ 0x38

The AM654 base board has a TCA9554/PCA9554-type GPIO expander on the
wkup_i2c0 bus at address 0x38 that is used to detect the presence of
daughter cards.  Add a respective DTS description of this expander
to enable its use.

Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
diff --git a/arch/arm/dts/k3-am654-base-board.dts b/arch/arm/dts/k3-am654-base-board.dts
index 248d60e..e73b9aa 100644
--- a/arch/arm/dts/k3-am654-base-board.dts
+++ b/arch/arm/dts/k3-am654-base-board.dts
@@ -76,4 +76,11 @@
 	pinctrl-names = "default";
 	pinctrl-0 = <&wkup_i2c0_pins_default>;
 	clock-frequency = <400000>;
+
+	tca9554: gpio@38 {
+		compatible = "nxp,pca9554";
+		reg = <0x38>;
+		gpio-controller;
+		#gpio-cells = <2>;
+	};
 };