Updated openstack/openstack
Project: openstack/neutron  948c34ead0f72ff60941f9541f7b71689a31975d
null
NSX plugin: fix get_gateway_devices

Fixes the error and adds relevant unit tests.
Also fixes get_gateway_devices signature for allowing
paging and sorting.

Closes-Bug: 1306301

Change-Id: Icb52a764e111365beaf4dc4fb4a5b8970a6cf887