ARM: dts: aspeed: Add AST2600 I3C control pins

Add pinctrl support for the I3C1 and I3C2 pins.
Signed-off-by: Dylan Hung <dylan_hung@aspeedtech.com>
Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au>
Link: https://lore.kernel.org/r/20230809134413.3614535-1-dylan_hung@aspeedtech.comSigned-off-by: Joel Stanley <joel@jms.id.au>

arch/arm/boot/dts/aspeed/aspeed-g6-pinctrl.dtsi

@@ -297,6 +297,16 @@ pinctrl_i2c9_default: i2c9_default {
 		groups = "I2C9";
 	};
 
+	pinctrl_i3c1_default: i3c1_default {
+		function = "I3C1";
+		groups = "I3C1";
+	};
+
+	pinctrl_i3c2_default: i3c2_default {
+		function = "I3C2";
+		groups = "I3C2";
+	};
+
 	pinctrl_i3c3_default: i3c3_default {
 		function = "I3C3";
 		groups = "I3C3";