tipc: simplify signature of tipc_nametbl_withdraw() functions

tipc: simplify signature of tipc_nametbl_withdraw() functions

Following the principles of the preceding commits, we reduce
the number of parameters passed along in tipc_sk_withdraw(),
tipc_nametbl_withdraw() and associated functions.

Signed-off-by: Jon Maloy <jmaloy@redhat.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Hoang Le <hoang.h.le@dektech.com.au>
Acked-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Acked-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>