13438 Update prototypes to 2021
Reviewed by: Andy Fiddaman <andy@omnios.org>
Reviewed by: Toomas Soome <tsoome@me.com>
Approved by: Robert Mustacchi <rm@fingolfin.org>

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  .\" 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>
  .\"
  .Dd Month Day, Year
  .Dt ENTRYNAME 9E
  .\" ENTRYNAME should be replaced with the primary entry point that you are
  .\" documenting. If there is more than one function, then you should either
--- 7,17 ----
  .\" 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 2021 <contributor>
  .\"
  .Dd Month Day, Year
  .Dt ENTRYNAME 9E
  .\" ENTRYNAME should be replaced with the primary entry point that you are
  .\" documenting. If there is more than one function, then you should either