Cases exist where you can request a port to be created, in such
a way where neutron has to defer assignment of addressing.
In Neutron's world, it wants to map the host so it can be ensured
that *correct* physical network is available and mapped to for the
address range. Networking-baremetal helps backfill physical connection
context so Neutron can make the appropriate address assignment.
In order to ensure we do the right thing while also ensuring
appropriate security around the state of the port and the bind,
we need to go ahead and facilitate an *initial* context
to neutron so address assignment can occur, but explicitly limits
the provided information to a highly limited scope to prevent
actual binding to a physical port.
With the assignment of addresses, it becomes possible to begin to
generate, or eventually *fix* network configuration metadata
being provided to a baremetal node.
In this *entire* process, we also identified you can create neutron
ports with binding information "out of the gate" to be immediately
bound. Thanks metalsmith! So the code pattern now checks the port,
and unbinds the VIF before rebinding it.
Related-Bug: #2106073
Change-Id: Ic53c626afe641ce63d71a7858e65df1fb250e3c0
5146e0a0f8