add a remote_dns port property

lib/App/Netdisco/DB/Result/DevicePort.pm

@@ -387,6 +387,14 @@ Returns the interface index (C<ifIndex>) of the port.
 
 sub ifindex { return (shift)->get_column('ifindex') }
 
+=head2 remote_dns
+
+Returns a hostname resolved from C<remote_ip> column.
+
+=cut
+
+sub remote_dns { return (shift)->get_column('remote_dns') }
+
 =head2 remote_inventory
 
 Returns a synthesized description of the remote LLDP device if inventory

lib/App/Netdisco/DB/Result/DevicePortProperties.pm

@@ -27,6 +27,8 @@ __PACKAGE__->add_columns(
   { data_type => "text", is_nullable => 1 },
   "remote_serial",
   { data_type => "text", is_nullable => 1 },
+  "remote_dns",
+  { data_type => "text", is_nullable => 1 },
   "raw_speed",
   { data_type => "bigint", default_value => 0, is_nullable => 1 },
   "faststart",