arm64: dts: uniphier: Stabilize Ethernet RGMII mode of PXs3 ref board

The RGMII PHY implemented in PXs3 ref board needs to change
drive-strength properties of the Ethernet Tx pins to stabilize the PHY.
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

arch/arm64/boot/dts/socionext/uniphier-pxs3-ref.dts

@@ -132,3 +132,19 @@ nand@0 {
 		reg = <0>;
 	};
 };
+
+&pinctrl_ether_rgmii {
+	tx {
+		pins = "RGMII0_TXCLK", "RGMII0_TXD0", "RGMII0_TXD1",
+		       "RGMII0_TXD2", "RGMII0_TXD3", "RGMII0_TXCTL";
+		drive-strength = <9>;
+	};
+};
+
+&pinctrl_ether1_rgmii {
+	tx {
+		pins = "RGMII1_TXCLK", "RGMII1_TXD0", "RGMII1_TXD1",
+		       "RGMII1_TXD2", "RGMII1_TXD3", "RGMII1_TXCTL";
+		drive-strength = <9>;
+	};
+};