First cut at supporting optional allowed_address_pairs option for Neutron Port update operation
diff --git a/openstack/networking/v2/ports/requests.go b/openstack/networking/v2/ports/requests.go
index 2caf1ca..52e6e43 100644
--- a/openstack/networking/v2/ports/requests.go
+++ b/openstack/networking/v2/ports/requests.go
@@ -168,12 +168,13 @@
 
 // UpdateOpts represents the attributes used when updating an existing port.
 type UpdateOpts struct {
-	Name           string
-	AdminStateUp   *bool
-	FixedIPs       interface{}
-	DeviceID       string
-	DeviceOwner    string
-	SecurityGroups []string
+	Name                string
+	AdminStateUp        *bool
+	FixedIPs            interface{}
+	DeviceID            string
+	DeviceOwner         string
+	SecurityGroups      []string
+	AllowedAddressPairs interface{}
 }
 
 // ToPortUpdateMap casts an UpdateOpts struct to a map.
@@ -198,6 +199,9 @@
 	if opts.Name != "" {
 		p["name"] = opts.Name
 	}
+	if opts.AllowedAddressPairs != nil {
+		p["allowed_address_pairs"] = opts.AllowedAddressPairs
+	}
 
 	return map[string]interface{}{"port": p}, nil
 }