misc: cleanup and fix --unknownopt issues

misc: cleanup and fix --unknownopt issues

Fixed checkusage.sh warnings:

  rtcwake: --unknownopt, non-empty stdout

  rtcwake: --unknownopt, stderr too long: 21
  blockdev: --unknownopt, stderr too long: 28
  lsipc: --unknownopt, stderr too long: 77
  pg: --unknownopt, stderr too long: 23
  renice: --unknownopt, stderr too long: 18
  sulogin: --unknownopt, stderr too long: 17
  write: --unknownopt, stderr too long: 12

Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>