watchdog: da9052_wdt: respect TWDMIN

We have to wait at least the minimium time for the watchdog window
(TWDMIN) before writings to the wdt register after the
watchdog is activated.
Otherwise the chip will assert TWD_ERROR and power down to reset mode.

Signed-off-by: Marcus Folkesson <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/da9052_wdt.c

···
 	da9052_wdt = &driver_data->wdt;
 
 	da9052_wdt->timeout = DA9052_DEF_TIMEOUT;
+	da9052_wdt->min_hw_heartbeat_ms = DA9052_TWDMIN;
 	da9052_wdt->info = &da9052_wdt_info;
 	da9052_wdt->ops = &da9052_wdt_ops;
 	da9052_wdt->parent = dev;