mx7dsabresd: Convert to watchdog driver model

Commit 68dcbdd594d4 ("ARM: imx: Add weak default reset_cpu()") caused
the 'reset' command in U-Boot to not cause a board reset.

Fix it by switching to the watchdog driver model via sysreset, which
is the preferred method for implementing the watchdog reset.

Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Marek Vasut <marex@denx.de>
diff --git a/arch/arm/dts/imx7d-sdb-u-boot.dtsi b/arch/arm/dts/imx7d-sdb-u-boot.dtsi
index b577730..71bfd80 100644
--- a/arch/arm/dts/imx7d-sdb-u-boot.dtsi
+++ b/arch/arm/dts/imx7d-sdb-u-boot.dtsi
@@ -2,6 +2,14 @@
 
 #include "imx7s-u-boot.dtsi"
 
+/ {
+	wdt-reboot {
+		compatible = "wdt-reboot";
+		wdt = <&wdog1>;
+		bootph-pre-ram;
+	};
+};
+
 &fec2 {
 	status = "disable";
 };
@@ -60,3 +68,7 @@
 		>;
 	};
 };
+
+&wdog1 {
+	bootph-pre-ram;
+};
diff --git a/configs/mx7dsabresd_defconfig b/configs/mx7dsabresd_defconfig
index 26e68d3..1c8105f 100644
--- a/configs/mx7dsabresd_defconfig
+++ b/configs/mx7dsabresd_defconfig
@@ -73,6 +73,8 @@
 CONFIG_SPI=y
 CONFIG_DM_SPI=y
 CONFIG_SOFT_SPI=y
+CONFIG_SYSRESET=y
+CONFIG_SYSRESET_WATCHDOG=y
 CONFIG_IMX_THERMAL=y
 CONFIG_USB=y
 CONFIG_USB_EHCI_HCD=y
@@ -85,4 +87,5 @@
 CONFIG_USB_GADGET_PRODUCT_NUM=0xa4a5
 CONFIG_CI_UDC=y
 CONFIG_USB_GADGET_DOWNLOAD=y
+CONFIG_IMX_WATCHDOG=y
 CONFIG_ERRNO_STR=y