PFKEYV2: Fix inconsistent typing in struct sadb_x_kmprivate.

Fixes inconsistent use of "uint32_t" vs. "u_int32_t".
Fix pfkeyv2 userspace builds.

Signed-off-by: Tushar Gohad <tgohad@mvista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Adrian Bunk <bunk@stusta.de>