watchdog: ziirave_wdt: Correct I2C device id to fix module autoloading.

The I2C core removes the manufacturer prefix from the compatible field
so it reports to user-space the uevent i2c:rave-wdt, but this doesn't
match with the i2c_device_id (i2c:ziirave-wdt) array so the module is not
autoloaded. Correct the I2C device id to match with the reported uevent
and fix the module autoloading functionality.

Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>