netconsole: remove a redundant netconsole_target_put()

This netconsole_target_put() is obviously redundant, and it
causes a kernel segfault when removing a bridge device which has
netconsole running on it.

This is caused by:

	commit 8d8fc29
	Author: Amerigo Wang <amwang@redhat.com>
	Date:   Thu May 19 21:39:10 2011 +0000

	    netpoll: disable netpoll when enslave a device

Cc: David Miller <davem@davemloft.net>
 (for all 3.x stable releases)
Cc: stable@vger.kernel.org
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/netconsole.c

@@ -643,7 +643,6 @@ static int netconsole_netdev_event(struct notifier_block *this,
 					__netpoll_cleanup(&nt->np);
 					dev_put(nt->np.dev);
 					nt->np.dev = NULL;
-					netconsole_target_put(nt);
 				}
 				nt->enabled = 0;
 				stopped = true;