Use dev-games/physfs instead of dev-libs/libzip to load compressed data

Packages describing “physfs” as local USE flag

Package “physfs” Flag Description
games-arcade/tuxanci Use dev-games/physfs instead of dev-libs/libzip to load compressed data
media-libs/sdl-sound Enable support for various formats through dev-games/physfs.
media-libs/allegro Enable physfs support

All packages providing a “physfs” USE flag (3)