Update FIP QoS Docs
Update FIP QoS Docs

This patch updates QoS docs to remove "port show" command
before associating Floating IP to port.
It is like that to be clear that QoS policy which is attached to
the FloatingIP is NOT visible in the port's attributes.

Change-Id: I127fbd25433e39905c3b83bbe914f027ab45ef3f
Closes-Bug: #1778740

openstack/neutron,mahak/neutron,mahak/neutron,mahak/neutron,openstack/neutron,noironetworks/neutron,openstack/neutron,noironetworks/neutron