[NETFILTER]: nf_conntrack_h323: fix ASN.1 types

1. Add support for decoding IPv6 address. I know it was manually added in
   the header file, but not in the template file. That wouldn't work.
2. Add missing support for decoding T.120 address in OLCA.
3. Remove unnecessary decoding of Information signal.

Signed-off-by: Jing Min Zhao <zhaojingmin@vivecode.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>