We allow connections to 8002 port in the admin network for
incoming connections from distributed serialization workers.
Distributed serialization workers should be installed and run
on slave and bootstrap nodes.
Change-Id: Idae764bde0b0dd482e6b08d69a97cd5d0717547d
Implements: blueprint distributed-serialization
(cherry picked from commit 97c9ca2c5f)
e0c44beaec