ebtables-translate: suppress redundant protocols

kernel would reject ip, ip6 etc. without -p ip, -p ip6.
So add it.  On reverse, search the match list to decide if -p
has to be translated or not.

Also, icmp and icmpv6 also imply l3 protocol, so no need to translate
that either.

Signed-off-by: Florian Westphal <fw@strlen.de>
6 files changed