If depending on the old subpackages of mesa-dri, apk is not smart enough
to determine that it should replace those old subpackages with the new
unified mesa-dri package, so we change the depends= in each reverse
dependency of those old subpackage names to force apk to purge the old
packages. As usual provides=/replaces= are a mystical art.

Also move freedreno to the ARM-only depends.