dt-bindings: watchdog: Add bindings for Intel Keem Bay SoC

Add Device Tree binding document for Watchdog IP in the Intel Keem Bay SoC.

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: Rob Herring <robh@kernel.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/8c4dad4fb8ba644607aa9379d5ec70d8707d7e75.1608141131.git.vijayakannan.ayyathurai@intel.com


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