opcua: use BASE_NONE instead of 0

Change-Id: I5ca5d41edf1f56b24da6360a10f0c6e2600572d2
Reviewed-on: https://code.wireshark.org/review/4150
Reviewed-by: Michael Mann <mmann78@netscape.net>
(cherry picked from commit 095a0e8b18ef93a6d4c1387bca3fed4596423b83)
Reviewed-on: https://code.wireshark.org/review/4242