Clean up the following clang-w1 warning:

kernel/reboot.c:587: warning: Function parameter or member
'poweroff_delay_ms' not described in 'hw_failure_emergency_poweroff'.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
---
 kernel/reboot.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/reboot.c b/kernel/reboot.c
index ed4e6dfb7d44..c18d9515a27f 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -579,6 +579,7 @@ static DECLARE_DELAYED_WORK(hw_failure_emergency_poweroff_work,
 
 /**
  * hw_failure_emergency_poweroff - Trigger an emergency system poweroff
+ * @poweroff_delay_ms: Shutdown delay time value.
  *
  * This may be called from any critical situation to trigger a system shutdown
  * after a given period of time. If time is negative this is not scheduled.
-- 
2.20.1.7.g153144c