i2c: i801: Create iTCO device on newer Intel PCHs

Starting from Intel Sunrisepoint (Skylake PCH) the iTCO watchdog resources
have been moved to reside under the i801 SMBus host controller whereas
previously they were under the LPC device.

In order to support the iTCO watchdog on newer PCHs we need to create the
platform device here in the SMBus driver and pass all known resources using
platform data.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Lee Jones <lee.jones@linaro.org>