91587326ae
Mesa generates a number of headers during build. To make Clang based documentation parsing work without depending on the generated headers, start a directory hierarchy under docs/header-stubs/ for static mock headers. Reviewed-by: Erik Faye-Lund <erik.faye-lund@collabora.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24507>
Mock headers and types used only for building documentation, to avoid a documentation dependency on generated headers, and to allow documentation of the generated types.