watchdog: docs: omap_wdt also understands nowayout

The omap_wdt kernel driver also understands the nowayout module
parameter. This updates the watchdog-parameters.txt to reflect this fact.
Signed-off-by: NLars Poeschel <poeschel@lemonage.de>
Reviewed-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NWim Van Sebroeck <wim@iguana.be>

Documentation/watchdog/watchdog-parameters.txt

@@ -208,6 +208,8 @@ nowayout: Watchdog cannot be stopped once started
 -------------------------------------------------
 omap_wdt:
 timer_margin: initial watchdog timeout (in seconds)
+nowayout: Watchdog cannot be stopped once started
+	(default=kernel config parameter)
 -------------------------------------------------
 orion_wdt:
 heartbeat: Initial watchdog heartbeat in seconds