Updating address pairs with xml doesn't work

Below command can't work because list element
"allowed_address_pairs" hasn't been updated
into the varaiable "attr.PLURALS"
"neutron port-update <port-uuid> \
--allowed-address-pairs list=true type=dict \
ip_address=10.0.0.1 --request-format xml"

Change-Id: I0d7dcca5f4848bc968f5c86fbeb46569c70c8fcd
Closes-Bug: #1229954