netfilter: nft_reject_bridge: enable reject with bridge vlan

Currently, using the bridge reject target with tagged packets
results in untagged packets being sent back.

Fix this by mirroring the vlan id as well.

Fixes: 85f5b308

 ("netfilter: bridge: add reject support")
Signed-off-by: Michael Braun <michael-dev@fami-braun.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>