Depending on the processing order of rules when installing in parallel,
these install rules might be processed before some other rule happens
to create the respective dirs. Make sure each one creates the needed
dirs before installing into them.
For arches that had their configure merged into the top-level, make
sure they don't still depend on a subdir configure script that no
longer exists. I had cleaned this up for some of the subdirs, but
these got lost in the shuffle.
