ARM: dts: pfla02: increase phy reset duration

Increase the reset duration to ensure correct phy functionality. The
reset duration is taken from barebox commit 52fdd510de ("ARM: dts:
pfla02: use long enough reset for ethernet phy"):

  Use a longer reset time for ethernet phy Micrel KSZ9031RNX. Otherwise a
  small percentage of modules have 'transmission timeouts' errors like

  barebox@Phytec phyFLEX-i.MX6 Quad Carrier-Board:/ ifup eth0
  warning: No MAC address set. Using random address 7e:94:4d:02:f8:f3
  eth0: 1000Mbps full duplex link detected
  eth0: transmission timeout
  T eth0: transmission timeout
  T eth0: transmission timeout
  T eth0: transmission timeout
  T eth0: transmission timeout

Cc: Stefan Christ <s.christ@phytec.de>
Cc: Christian Hemp <c.hemp@phytec.de>
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Fixes: 3180f956 ("ARM: dts: Phytec imx6q pfla02 and pbab01 support")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm/boot/dts/imx6qdl-phytec-pfla02.dtsi

@@ -91,6 +91,7 @@ &fec {
 	pinctrl-0 = <&pinctrl_enet>;
 	phy-handle = <&ethphy>;
 	phy-mode = "rgmii";
+	phy-reset-duration = <10>; /* in msecs */
 	phy-reset-gpios = <&gpio3 23 GPIO_ACTIVE_LOW>;
 	phy-supply = <&vdd_eth_io_reg>;
 	status = "disabled";