i40iw: Correctly fail loopback connection if no listener

Fail the connect and return the proper error code if a client
is started with local IP address and there is no corresponding
loopback listener.

Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>