12310 Add demangle(1) command

*** 9,18 ****
--- 9,19 ----
  # http://www.illumos.org/license/CDDL.
  #
  
  #
  # Copyright 2017 Jason King
+ # Copyright 2019 Joyent, Inc.
  #
  
  #
  # MAPFILE HEADER START
  #
*** 28,36 ****
--- 29,38 ----
  #
  $mapfile_version 2
  
  SYMBOL_VERSION ILLUMOSprivate {
      global:
+         sysdem_parse_lang;
          sysdemangle;
      local:
          *;
  };