Currently, ClocksPerSec is determined by exec'ing getconf in func init,
i.e. on startup of every program importing the package. getconf might
not be present on some systems or is not executable by the current user.
To avoid this hard to control dependency, use the
github.com/tklauser/go-sysconf package which implements sysconf(3)
entirely in Go without cgo. The package is supported on all platforms
currently supported by the cpu and v3/cpu package of gopsutil.