Add a small patch to fix FTBFS

The build was failing with: retro-gtk/meson.build:188:4: ERROR: Got unknown keyword arguments "export_packages", "namespace"

Checking https://mesonbuild.com/Pkgconfig-module.html the arguments "export_packages" and "namespace" are not present in pkg.generate, so I removed them to make the build complete

Closes: 998613