scsi: fix missing include linux/types.h in scsi_netlink.h

scsi: fix missing include linux/types.h in scsi_netlink.h

Thomas Bork reported that commit c6203cd ("scsi: use __uX
types for headers exported to user space") caused a regression
as now he's getting this warning :

> /usr/src/linux-2.6.32-eisfair-1/usr/include/scsi/scsi_netlink.h:108:
> found __[us]{8,16,32,64} type without #include <linux/types.h>

This issue was addressed later by commit 10db4e1 ("headers:
include linux/types.h where appropriate"), so let's just pick the
relevant part from it.

Cc: Thomas Bork <tom@eisfair.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>