In /usr/bin/printafm line 9:
gs="`dirname \"$0\"`/$GS_EXECUTABLE"
    ^--------------^ SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
gs="$(dirname \"$0\")/$GS_EXECUTABLE"

For more information:
  https://www.shellcheck.net/wiki/SC2006 -- Use $(...) notation instead of le...