tipc: Delete tipc_ownidentity()

Moves the content of the native API routine tipc_ownidentity() into the
sole routine that calls it, since it can no longer be called in isolation.

Signed-off-by: Allan Stephens <Allan.Stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>