If the watchdog was already enabled by the BIOS after booting, the
watchdog infrastructure needs to regularly send keepalives to
prevent a unexpected reset.
WDOG_ACTIVE only serves as an status indicator for userspace,
we want to use WDOG_HW_RUNNING instead.

Since my Fujitsu Esprimo P720 does not support the watchdog,
this change is compile-tested only.
Suggested-by: Guenter Roeck <linux@roeck-us.net>
Fixes: fb551405 (watchdog: sch56xx: Use watchdog core)
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20220131211935.3656-5-W_Armin@gmx.deReviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>