[ntp/f21] (3 commits) ...4.2.6p5-23

[Miroslav Lichvar]

Summary of changes:

  49b8543... don't print exit status (#1050148) (*)
  375ae7e... add nanosecond support to SHM refclock (*)
  f25d638... 4.2.6p5-23 (*)

(*) This commit already existed in another branch; no separate mail sent