powerpc/numa: Add form 1 NUMA affinity

Firmware changed the way it represents memory and cpu affinity on POWER7.
Unfortunately the old method now caps the topology to work around issues
with legacy operating systems. For Linux to get the correct topology we
need to use the new form 1 affinity information.

We set the form 1 field in the client architecture, and if we see "1" in the
ibm,associativity-form property firmware supports form 1 affinity and
we should look at the first field in the ibm,associativity-reference-points
array. If not we use the second field as we always have.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>