xtables-compat: skip unsupported tables

Instead of not listing anything at all if an unknown table name
exists, just skip them.  Output a small comment that the listing
doesn't include the (unrecognized, nft-created) tables.

Next patch will restrict 'is this table printable in
xtables syntax' check to the "builtin" tables.

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