tcl: prevent installing another copy of tzdata

It checks build host filesystem and if it doesn't find UTC or GMT
files it installs another copy of tzdata files in:
/usr/lib/tcl8.6/tzdata

Buildhistory shows the difference:
-PKGSIZE = 2227075
+PKGSIZE = 3433088

See the autodetection in configure.in:
  #------------------------------------------------------------------------
  #       Check whether the timezone data is supplied by the OS or has
  #       to be installed by Tcl. The default is autodetection, but can
  #       be overridden on the configure command line either way.
  #------------------------------------------------------------------------

  AC_MSG_CHECKING([for timezone data])
  AC_ARG_WITH(tzdata,
      AC_HELP_STRING([--with-tzdata],
          [install timezone data (default: autodetect)]),
      [tcl_ok=$withval], [tcl_ok=auto])

  #
  # Any directories that get added here must also be added to the
  # search path in ::tcl::clock::Initialize (library/clock.tcl).
  #
  case $tcl_ok in
      no)
          AC_MSG_RESULT([supplied by OS vendor])
      ;;
      yes)
          # nothing to do here
      ;;
      auto*)
          AC_CACHE_VAL([tcl_cv_dir_zoneinfo], [
          for dir in /usr/share/zoneinfo \
                  /usr/share/lib/zoneinfo \
                  /usr/lib/zoneinfo
          do
                  if test -f $dir/UTC -o -f $dir/GMT
                  then
                          tcl_cv_dir_zoneinfo="$dir"
                          break
                  fi
          done])
          if test -n "$tcl_cv_dir_zoneinfo"; then
              tcl_ok=no
              AC_MSG_RESULT([$dir])
          else
              tcl_ok=yes
          fi
      ;;
      *)
          AC_MSG_ERROR([invalid argument: $tcl_ok])
      ;;
  esac
  if test $tcl_ok = yes
  then
      AC_MSG_RESULT([supplied by Tcl])
      INSTALL_TZDATA=install-tzdata
  fi

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit 3ace9fbf)
Signed-off-by: Steve Sakoman <steve@sakoman.com>