74d5e01bb4
The meson gate that enables EGL on Redox — adding "redox" to system_has_kms_drm (meson.build:159, so with_dri→with_egl/gbm) and to the _GNU_SOURCE platform list (:1208) — existed only as an in-place edit in the untracked extracted source/ tree. Any clean re-extract lost it and reverted to "Feature egl cannot be enabled". Capture it as local/patches/mesa/08-*.patch and wire it into recipe.toml so EGL/GBM/llvmpipe build reproducibly. Source tree reverted to pristine so the patch is the sole, tracked change.