13438 Update prototypes to 2021

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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>
  #