- Don't add extra compiler flags.
    - Package the CUPS driver in sbindir and put a symlink in the CUPS
        ServerBin directory to work around bug #231015.
    - Disable libgutenprintui (GTK+ 1.2 library). Build requires gtk2-devel,
        not gtk+-devel.
    - No longer need PPDs sub-packages: CUPS driver is included in the cups
        sub-package.