under OpenBSD 6.0, KERN_RND is no more

http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/sys/sysctl.h?rev=1.162&content-type=text/x-cvsweb-markup
http://cvsweb.openbsd.org/cgi-bin/cvsweb/src/sys/sys/sysctl.h.diff?r1=1.161&r2=1.162

src/unix/bsd/openbsdlike/openbsd.rs

@@ -313,7 +313,6 @@ pub const KERN_OSVERSION: ::c_int = 27;
 pub const KERN_SOMAXCONN: ::c_int = 28;
 pub const KERN_SOMINCONN: ::c_int = 29;
 pub const KERN_USERMOUNT: ::c_int = 30;
-pub const KERN_RND: ::c_int = 31;
 pub const KERN_NOSUIDCOREDUMP: ::c_int = 32;
 pub const KERN_FSYNC: ::c_int = 33;
 pub const KERN_SYSVMSG: ::c_int = 34;