watchdog: ensure that module is loaded as early as possible

watchdog: ensure that module is loaded as early as possible

It is expected that a watchdog module will disable an active watchdog when
its probe is called ie, when it is loaded. So an early load of the module
will help to disable it earlier.
This can be helpful in some corner cases where kdump and watchdog daemon
both are active.

Testing:
    -- When watchdog kernel modules were added
	# dracut --no-hostonly initramfs-test.img -a watchdog
	# lsinitrd initramfs-test.img -f etc/cmdline.d/00-watchdog.conf
 	rd.driver.pre=iTCO_wdt,lpc_ich,

Signed-off-by: Pratyush Anand <panand@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Harald Hoyer <harald@redhat.com>