gnupod: fix variants

[ryandesign (Ryan Carsten Schmidt)]

The gnupod port has variants that only add dependencies:

# should also use timidity
variant flac description "Enable FLAC" {
    depends_lib-append  port:flac port:p5.12-audio-flac-header
}

# should use Ogg::Vorbis::Header::PurePerl, won't work
variant vorbis description "Enable Ogg/Vorbis" {
    depends_lib-append  port:vorbis-tools port:p5.12-libvorbis-perl
}

variant aac description "Enable AAC" {
    depends_lib-append  port:faac path:lib/libavcodec.dylib:ffmpeg
}

variant artwork description "Enable artwork support" {
    depends_lib-append  port:ImageMagick
}

The port needs to be updated to ensure that those dependencies will not be used if those variants are not selected, even if those ports are already installed.

[mf2k (Frank Schima)]

This port is no longer maintained.