- Reset maintainership per skreuzer.
- Install desktop and icon files when GNOME or GTK option is set. 
- Fix pidfile when 'distccd_flags' variable is not set by the user.
- Replace COMPILER_LINKS option with CLANGLINK and LLVMLINK options. Note
these are turned off by default unlike COMPILER_LINKS. Actually, these are
equivalent to options for devel/ccache as they are often jointly used.
- Modernize and clean up the port.
PR: 185426