There is actually no need to ping the watchdog before disabling it
during timeout change. Disabling the watchdog already takes care of
resetting the counter.

This fixes an issue during boot when the userspace watchdog handler takes
over and the watchdog is already running. Opening the watchdog in this case
leads to the first ping and directly after that without the required
heartbeat delay a second ping issued by the set_timeout call. Due to the
missing delay this resulted in a reset.
Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com>
Link: https://lore.kernel.org/r/20200403130728.39260-3-s.riedmueller@phytec.deSigned-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>