In ncp_conn_alloc(), a new credential pointer, 'owner', is set up to point
at the credential to be used by the connection. However, the pointer's
value was ignored when actually setting hcp->nc_owner.

(1) Do set nc_owner to the owner pointer value so that the credential is

not discarded after being carefully configured.

(2) In the case where we create a new credential with modified uid, copy

the existing credential to initialize non-uid fields to existing
values, which will lead to a fully initialized MAC label, groups, etc.

Found with: Coverity Prevent(tm)
CID: 2226