Remove a useless block in the shebang checks.

• Once upon a time, we checked all of STAGEDIR/PREFIX's executable files.
• We then decided too many false positives were found, so we switched to only checking executable files in bin/sbin/libexec/www, and also symlinks that were in there.
• And then, we decided to go back to check all of STAGEDIR/PREFIX's executable files, but forgot to remove the checks for symlinks (which are now useless because we already check all the executable files.)

Reported by: lifanov
Sponsored by: Absolight