ARM: dts: imx6-tx6: specify ethernet phy reset post-delay

Under certain circumstances the ethernet PHY cannot be detected on
Ka-Ro electronics TX6 modules. Using a phy-reset-post-delay of at least
2ms alleviates this problem. Define it to 10ms to be on the safe side.
Signed-off-by: Lothar Waßmann <LW@KARO-electronics.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-tx6.dtsi

@@ -249,6 +249,7 @@ &fec {
 	clock-names = "ipg", "ahb", "ptp", "enet_out";
 	phy-mode = "rmii";
 	phy-reset-gpios = <&gpio7 6 GPIO_ACTIVE_LOW>;
+	phy-reset-post-delay = <10>;
 	phy-handle = <&etnphy>;
 	phy-supply = <&reg_3v3_etn>;
 	status = "okay";