watchdog: Add watchdog driver for Intel Keembay Soc

Intel Keembay Soc requires watchdog timer support.
Add watchdog driver to enable this.

Acked-by: Mark Gross <mgross@linux.intel.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Vijayakannan Ayyathurai <vijayakannan.ayyathurai@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/26d74f46ce74488424371dd3e16aa38508fa6c2e.1608141131.git.vijayakannan.ayyathurai@intel.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>