watchdog: rti-wdt: fix reference leak in rti_wdt_probe

watchdog: rti-wdt: fix reference leak in rti_wdt_probe

pm_runtime_get_sync() will increment pm usage counter even it
failed. Forgetting to call pm_runtime_put_noidle will result
in reference leak in rti_wdt_probe, so we should fix it.

Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20201030154909.100023-1-zhangqilong3@huawei.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>