wmakeLnInclude: improvements and bugfix

  - fixed typo: had skipped '-Make' instead of 'Make' directory

  - remove broken links first
    * helps when file locations have changed

  - filter out trailing 'lnInclude' from the <dir> spec
    * this makes it easier to update existing lnInclude dirs:
         find -name lnInclude -exec wmakeLnInclude -f {} \;

  - reduced output noise when re-creating an identical link