do not stop health check before sending signal

Docker daemon always stops healthcheck before sending signal to a
container now. However, when we use "docker kill" to send signals
other than SIGTERM or SIGKILL to a container, such as SIGINT,
daemon still stops container health check though container process
handles the signal normally and continues to work.

Signed-off-by: Ruilin Li <liruilin4@huawei.com>

daemon/kill.go

@@ -64,8 +64,6 @@ func (daemon *Daemon) killWithSignal(container *containerpkg.Container, sig int)
 	container.Lock()
 	defer container.Unlock()
 
-	daemon.stopHealthchecks(container)
-
 	if !container.Running {
 		return errNotRunning(container.ID)
 	}