Use SysctlUvmexp from golang.org/x/sys/unix to avoid having to define the type Uvmexp and the sysctl consts. This will also allow to build on GOOS=openbsd with e.g. GOARCH=arm64. Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
This code is based on the FreeBSD version and implements roughly the same feature set.