watchdog: pika_wdt: drop pointless static qualifier in pikawdt_init

There is no need to have the 'post1' variable static since
new value always be assigned before use it.

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