watchdog: WatchDog Timer Driver Core - Add basic framework

The WatchDog Timer Driver Core is a framework
that contains the common code for all watchdog-driver's.
It also introduces a watchdog device structure and the
operations that go with it.

This is the introduction of this framework. This part
supports the minimal watchdog userspace API (or with
other words: the functionality to use /dev/watchdog's
open, release and write functionality as defined in
the simplest watchdog API). Extra functionality will
follow in the next set of patches.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>

diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 9eaa212..55bd574 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -2,6 +2,10 @@
 # Makefile for the WatchDog device drivers.
 #
 
+# The WatchDog Timer Driver Core.
+watchdog-objs	+= watchdog_core.o watchdog_dev.o
+obj-$(CONFIG_WATCHDOG_CORE)	+= watchdog.o
+
 # Only one watchdog can succeed. We probe the ISA/PCI/USB based
 # watchdog-cards first, then the architecture specific watchdog
 # drivers and then the architecture independent "softdog" driver.