SUNRPC: rpc_clnt_set_transport() must not change the autobind setting

The autobind setting was supposed to be determined in rpc_create(),
since commit c2866763 ("SUNRPC: use sockaddr + size when creating
remote transport endpoints").

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>