netfilter: IPv6: fix DSCP mangle code

The mask indicates the bits one wants to zero out, so it needs to be
inverted before applying to the original TOS field.

Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1 file changed