12167 Update prototypes to 2020

*** 7,13 ****
  .\" A full copy of the text of the CDDL should have accompanied this
  .\" source.  A copy of the CDDL is also available via the Internet at
  .\" http://www.illumos.org/license/CDDL.
  .\"
  .\"
! .\" Copyright 2019 <contributor>
  .\"
--- 7,13 ----
  .\" A full copy of the text of the CDDL should have accompanied this
  .\" source.  A copy of the CDDL is also available via the Internet at
  .\" http://www.illumos.org/license/CDDL.
  .\"
  .\"
! .\" Copyright 2020 <contributor>
  .\"