Ethernet : modify tx and rx delay for RK3288

tx = 0x25 , rx = 0x17

Change-Id: I0990095050bf2c5748c47bdb5164ec334cffa309

Author: yupei_lin

arch/arm/boot/dts/rk3288-tinker-board.dtsi

@@ -204,8 +204,8 @@
 	assigned-clock-parents = <&ext_gmac>;
 	pinctrl-names = "default";
 	pinctrl-0 = <&rgmii_pins>;
-	tx_delay = <0x30>;
-	rx_delay = <0x10>;
+	tx_delay = <0x25>;
+	rx_delay = <0x17>;
 	status = "okay";
 };