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 8d8fc29d02a33e4bd5f4fa47823c1fd386346093
Author: Amerigo Wang <[e-mail]>
Date: Thu May 19 21:39:10 2011 +0000

netpoll: disable netpoll when enslave a device

Cc: David Miller <[e-mail]>
(for all 3.x stable releases)
Cc: [e-mail]
Signed-off-by: Cong Wang <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/netconsole.c

···
 					__netpoll_cleanup(&nt->np);
 					dev_put(nt->np.dev);
 					nt->np.dev = NULL;
-					netconsole_target_put(nt);
 				}
 				nt->enabled = 0;
 				stopped = true;