netconsole: remove a redundant netconsole_target_put()

commit 72d3eb13b5c0abe7d63efac41f39c5b644c7bbaa upstream.

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 <amwang@redhat.com>
	Date:   Thu May 19 21:39:10 2011 +0000

	    netpoll: disable netpoll when enslave a device

Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>