[NETFILTER]: nfnetlink_log: fix byteorder of NFULA_SEQ_GLOBAL

NFULA_SEQ_GLOBAL should be in network byteorder.

Spotted by Al Viro.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>