arm64: dts: meson: sm1: add Ethernet PHY reset line for ODROID-C4/HC4

This patch is to fix an issue that the ethernet link doesn't come up
when using ip link set down/up:
   [   11.428114] meson8b-dwmac ff3f0000.ethernet eth0: Link is Down
   [   14.428595] meson8b-dwmac ff3f0000.ethernet eth0: PHY [0.0:00] driver [RTL8211F Gigabit Ethernet] (irq=31)
   [   14.428610] meson8b-dwmac ff3f0000.ethernet: Failed to reset the dma
   [   14.428974] meson8b-dwmac ff3f0000.ethernet eth0: stmmac_hw_setup: DMA engine initialization failed
   [   14.711185] meson8b-dwmac ff3f0000.ethernet eth0: stmmac_open: Hw setup failed

This fix refers to two commits applied for ODROID-N2 (G12B).
    commit 658e4129 ("arm64: dts: meson: g12b: odroid-n2: add the Ethernet PHY reset line")
    commit 1c741253 ("arm64: dts: meson: g12b: odroid-n2: fix PHY deassert timing requirements")

Fixes: 88d537bc ("arm64: dts: meson: convert meson-sm1-odroid-c4 to dtsi")
Signed-off-by: Dongjin Kim <tobetter@gmail.com>
Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
[narmstrong: added fixes tag and typo in commit log]
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lore.kernel.org/r/YScKYFWlYymgGw3l@anyang-linuxfactory-or-kr

arch/arm64/boot/dts/amlogic/meson-sm1-odroid.dtsi

@@ -263,6 +263,10 @@ external_phy: ethernet-phy@0 {
 		reg = <0>;
 		max-speed = <1000>;
 
+		reset-assert-us = <10000>;
+		reset-deassert-us = <80000>;
+		reset-gpios = <&gpio GPIOZ_15 (GPIO_ACTIVE_LOW | GPIO_OPEN_DRAIN)>;
+
 		interrupt-parent = <&gpio_intc>;
 		/* MAC_INTR on GPIOZ_14 */
 		interrupts = <26 IRQ_TYPE_LEVEL_LOW>;