watchdog: Automatically register device with sysreset

Add an option to automatically register watchdog devices with the
wdt_reboot driver for use with sysreset. This allows sysreset to be a
drop-in replacement for platform-specific watchdog reset code, without
needing any device tree changes.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/drivers/sysreset/Kconfig b/drivers/sysreset/Kconfig
index de75c9c..f6d6003 100644
--- a/drivers/sysreset/Kconfig
+++ b/drivers/sysreset/Kconfig
@@ -131,6 +131,13 @@
 	help
 	  Reboot support for generic watchdog reset.
 
+config SYSRESET_WATCHDOG_AUTO
+	bool "Automatically register first watchdog with sysreset"
+	depends on SYSRESET_WATCHDOG
+	help
+	  If enabled, the first watchdog (as selected by the watchdog uclass)
+	  will automatically be registered with the watchdog reboot driver.
+
 config SYSRESET_RESETCTL
 	bool "Enable support for reset controller reboot driver"
 	select DM_RESET