sys/param.h is needed for __FreeBSD_version.
Pointed out by Juergen, thanks.
Signed-off-by: NAndreas Faerber <andreas.faerber@web.de>
Cc: Juergen Lock <nox@jelal.kn-bremen.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>