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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   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   */
  
  /*
!  * Copyright 2020 <contributor>
   */
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   * source.  A copy of the CDDL is also available via the Internet at
   * http://www.illumos.org/license/CDDL.
   */
  
  /*
!  * Copyright 2021 <contributor>
   */