cpuallocator: add basic CPU clustering support.

Try to satisfy satisfy allocation requests consuming one
or more full CPU clusters before falling back to smaller
blocks of allocation. Try to squeeze the full allocation
into a single die or a single package. Don't attempt any
cluster-based allocation if neither of these is possible.

Satisfy low-prio allocations using E-core clusters only.
Use P-core clusters only to satisfy priority preferences
above low-prio.

Signed-off-by: Krisztian Litkey <krisztian.litkey@intel.com>