Generate gir without link attribute

When trying to support linking against gstreamer-full we need to override the library names that are linked against it. This should be handled by system-deps but gir is adding an extra #[link] attribute to the generation that makes it difficult to rename libraries. This MR regenerates files without this attribute. All of the context for this change and all of the alternatives we considered are explained in gtk-rs-core#1508.

Related MRs

• Blocked on: gir#1600, gtk-rs-core#1508
• Also related: gstreamer TODO, meson TODO