tipc: simplify signature of tipc_service_find_range()

We simplify the signatures of the functions tipc_service_create_range()
and tipc_service_find_range().

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>