watchdog: imx: add config to disable wdog reset

Add Kconfig option WATCHDOG_RESET_DISABLE to disable watchdog reset
in imx_watchdog driver, so that the watchdog will not be fed in
u-boot if CONFIG_WATCHDOG_RESET_DISABLE is enabled.

Signed-off-by: Xiaoliang Yang <xiaoliang.yang_1@nxp.com>
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index b6974ad..10fd303 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -11,6 +11,12 @@
 config HW_WATCHDOG
 	bool
 
+config WATCHDOG_RESET_DISABLE
+	bool "Disable reset watchdog"
+	help
+	   Disable reset watchdog, which can let WATCHDOG_RESET invalid, so
+	   that the watchdog will not be fed in u-boot.
+
 config BCM2835_WDT
 	bool "Enable BCM2835/2836 watchdog driver"
 	select HW_WATCHDOG