Fixes FTBFS on kfreebsd-*
Author: Petr Salinger <Petr.Salinger@seznam.cz>
--- a/src/getsize.c
+++ b/src/getsize.c
@@ -87,7 +87,7 @@ error:
     return -1;
 }
 
-#elif defined(__FreeBSD__)
+#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 /* scrub-1.7 tested freebsd 5.3-RELEASE-p5 */
 #include <sys/ioctl.h>
 #include <sys/disk.h>
