watchdog: renesas-wdt: add driver

Add support for watchdogs (RWDT and SWDT) found on RCar Gen3 based SoCs
from Renesas.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index fb94765..3902c9c 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -661,6 +661,14 @@
 	  To compile this driver as a module, choose M here: the
 	  module will be called atlas7_wdt.
 
+config RENESAS_WDT
+	tristate "Renesas WDT Watchdog"
+	depends on ARCH_RENESAS || COMPILE_TEST
+	select WATCHDOG_CORE
+	help
+	  This driver adds watchdog support for the integrated watchdogs in the
+	  Renesas R-Car and other SH-Mobile SoCs (usually named RWDT or SWDT).
+
 # AVR32 Architecture
 
 config AT32AP700X_WDT