Add a missing #include for FreeBSD hosts

Signed-off-by: Juergen Lock <nox@jelal.kn-bremen.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
diff --git a/qemu-timer.c b/qemu-timer.c
index 49eac86..e6076ca 100644
--- a/qemu-timer.c
+++ b/qemu-timer.c
@@ -35,6 +35,9 @@
 #include <errno.h>
 #include <sys/time.h>
 #include <signal.h>
+#ifdef __FreeBSD__
+#include <sys/param.h>
+#endif
 
 #ifdef __linux__
 #include <sys/ioctl.h>