Implements the port data plane status extension. Third parties
can report via Neutron API issues in the underlying data plane
affecting connectivity from/to Neutron ports.
Supported statuses:
- None: no status being reported; default value
- ACTIVE: all is up and running
- DOWN: no traffic can flow from/to the Neutron port
Setting attribute available to admin or any user with specific role
(default role: data_plane_integrator).
ML2 extension driver loaded on request via configuration:
[ml2]
extension_drivers = data_plane_status
Related-Bug: #1598081
Related-Bug: #1575146
DocImpact: users can get status of the underlying port data plane;
attribute writable by admin users and users granted the
'data-plane-integrator' role.
APIImpact: port now has data_plane_status attr, set on port update
Implements: blueprint port-data-plane-status
Depends-On: I04eef902b3310f799b1ce7ea44ed7cf77c74da04
Change-Id: Ic9e1e3ed9e3d4b88a4292114f4cb4192ac4b3502