nft: scanner: fixed problem with ipv6 address

nft: scanner: fixed problem with ipv6 address

There is a problem with the follow ipv6 address combination:

nft add rule ip6 t_ip61 filter-input ip6 saddr ::1234:1234:1234:1234:1234:1234:1234

1234::1234:1234:1234:1234:1234:1234
1234:1234::1234:1234:1234:1234:1234
1234:1234:1234::1234:1234:1234:1234
1234:1234:1234:1234::1234:1234:1234
1234:1234:1234:1234:1234::1234:1234
::1234:1234:1234:1234:1234:1234
1234::1234:1234:1234:1234:1234
1234:1234::1234:1234:1234:1234
1234:1234:1234::1234:1234:1234
1234:1234:1234:1234::1234:1234
::1234:1234:1234:1234:1234
1234::1234:1234:1234:1234
1234:1234::1234:1234:1234
1234:1234:1234::1234:1234
::1234:1234:1234:1234
1234::1234:1234:1234
1234:1234::1234:1234
::1234:1234:1234
1234::1234:1234

The problem was in the scanner (src/scanner.l). Several brackets were missed
and the result was an incorrect interpretation.

Fix it by adding some brackets in a regular expression in src/scanner.l

Signed-off-by: Ana Rey <anarey@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>