netfilter: fix some sparse endianess warnings

net/netfilter/xt_NFQUEUE.c:46:9: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:46:9:    expected unsigned int [unsigned] [usertype] ipaddr
net/netfilter/xt_NFQUEUE.c:46:9:    got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:68:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:68:10:    expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:68:10:    got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:69:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:69:10:    expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:69:10:    got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:70:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:70:10:    expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:70:10:    got restricted unsigned int
net/netfilter/xt_NFQUEUE.c:71:10: warning: incorrect type in assignment (different base types)
net/netfilter/xt_NFQUEUE.c:71:10:    expected unsigned int [unsigned] <noident>
net/netfilter/xt_NFQUEUE.c:71:10:    got restricted unsigned int

net/netfilter/xt_cluster.c:20:55: warning: incorrect type in return expression (different base types)
net/netfilter/xt_cluster.c:20:55:    expected unsigned int
net/netfilter/xt_cluster.c:20:55:    got restricted unsigned int const [usertype] ip
net/netfilter/xt_cluster.c:20:55: warning: incorrect type in return expression (different base types)
net/netfilter/xt_cluster.c:20:55:    expected unsigned int
net/netfilter/xt_cluster.c:20:55:    got restricted unsigned int const [usertype] ip

Signed-off-by: Patrick McHardy <kaber@trash.net>