netfilter 09/09: remove padding from struct xt_match on 64bit builds

reorder struct xt_match to remove 8 bytes of padding and make its size
128 bytes.

This saves a small amount of data space in each of the xt netfilter
modules and fits xt_match in one 128 byte cache line.

Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>