[TL install] Confusing final message in case of symlinks

[Denis Bitouzé]

Hi,

if the one the option:

- "create symlinks to standard directories" (text install)
- "Create symlinks in system directories" (GUI install)

(BTW, why not the same string?) has been chosen, the final message:

  ┌────
  │ Add /usr/local/texlive/2019/texmf-dist/doc/man to MANPATH.
  │ Add /usr/local/texlive/2019/texmf-dist/doc/info to INFOPATH.
  │ Most importantly, add /usr/local/texlive/2019/bin/x86_64-linux
  │ to your PATH for current and future sessions.
  └────

should not be displayed, as it is confusing and would lead to useless
extra configurations.
-- 
Denis