watchdog: keembay: Upadate WDT pretimeout for every update in timeout

The pre-timeout value to be programmed to the register has to be
calculated and updated for every change in the timeout value.
Else the threshold time wouldn't be calculated to its
corresponding timeout.

Fixes: fa0f8d51 ("watchdog: Add watchdog driver for Intel Keembay Soc")
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Kris Pan <kris.pan@intel.com>
Signed-off-by: Shruthi Sanil <shruthi.sanil@intel.com>
Link: https://lore.kernel.org/r/20210517174953.19404-3-shruthi.sanil@intel.com


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