drivers: watchdog: marvell_gti: fix zero pretimeout handling

When pretimeout is set to 0 then do not reprogram timer
with zero timeout, this will reset device immediately.
Also disable interrupt to stop pretimeout notification.

Signed-off-by: Bharat Bhushan <bbhushan2@marvell.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20231009044037.514570-1-bbhushan2@marvell.com


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