odp-netlink.h: Use 32-bit aligned 64-bit types.

odp-netlink.h: Use 32-bit aligned 64-bit types.

Open vSwitch userspace uses special types to indicate that a particular
object may not be naturally aligned.  Netlink is one source of such
problems: in Netlink, 64-bit integers are often aligned only on 32-bit
boundaries.  This commit changes the odp-netlink.h that is transformed from
<linux/openvswitch.h> to use these types to make it harder to accidentally
access a misaligned 64-bit member.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>