netlink_linearize: use range expression for OP_EQ and OP_IMPLICIT

netlink_linearize: use range expression for OP_EQ and OP_IMPLICIT

range expression is available since v4.9-rc1~127^2~67^2~3, replace the
two cmp expression when generating netlink bytecode.

Code to delinearize the two cmp expressions to represent the range
remains in place for backwards compatibility.

The delinearize path to parse range expressions with NFT_OP_EQ is
already present since:

 3ed932917cc7 ("src: use new range expression for != [a,b] intervals")

Update tests/py payload accordingly, json tests need no update since
they already use the range to represent them.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>