Currently the tacker connection point (CP) support Virtural IP only if
the security group is off (via anti_spoofing_protection off).
But it's good to have both by supporting allowed_address_pairs.
This RFE is for this purpose.
Closes-Bug: #1664805
Change-Id: I9fa1d4b69f8cbf51b047110cd6cfa61fb91a0bf0