watchdog: Make watchdog core configurable as module

Under some circumstances it may be desirable to configure
the watchdog core as module. Enable it.

As part of this change, mark pretimeout governors as depending
on the watchdog core. This is necessary to prevent governors
from being built into the kernel if the watchdog core is built
as module.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

drivers/watchdog/Kconfig

@@ -30,7 +30,7 @@ menuconfig WATCHDOG
 if WATCHDOG
 
 config WATCHDOG_CORE
-	bool "WatchDog Timer Driver Core"
+	tristate "WatchDog Timer Driver Core"
 	---help---
 	  Say Y here if you want to use the new watchdog timer driver core.
 	  This driver provides a framework for all watchdog timer drivers
@@ -75,6 +75,7 @@ if WATCHDOG_PRETIMEOUT_GOV
 
 config WATCHDOG_PRETIMEOUT_GOV_NOOP
 	tristate "Noop watchdog pretimeout governor"
+	depends on WATCHDOG_CORE
 	default WATCHDOG_CORE
 	help
 	  Noop watchdog pretimeout governor, only an informational
@@ -82,6 +83,7 @@ config WATCHDOG_PRETIMEOUT_GOV_NOOP
 
 config WATCHDOG_PRETIMEOUT_GOV_PANIC
 	tristate "Panic watchdog pretimeout governor"
+	depends on WATCHDOG_CORE
 	default WATCHDOG_CORE
 	help
 	  Panic watchdog pretimeout governor, on watchdog pretimeout