netfilter: nft_compat: set IP6T_F_PROTO flag if protocol is set
netfilter: nft_compat: set IP6T_F_PROTO flag if protocol is set

ip6tables extensions check for this flag to restrict match/target to a
given protocol. Without this flag set, SYNPROXY6 returns an error.

Signed-off-by: Pablo Neira Ayuso <707d14912bb250caf67dfe0ea4035681fbfc4f56@netfilter.org>
Acked-by: Patrick McHardy <3a4d625ce225e891399f98db96a382ac4a84080b@trash.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs