Probe for GICv3 re-distributors on core bring-up

Probe for GICv3 re-distributors on core bring-up

The GICv3 distributor can have more ports than CPUs are available in
the system. Probe all re-distributors and use the matching affinity
levels as specified by each core and re-distributor to decide which
re-distributor to use with which CPU core.

If a core cannot be matched with a re-distributor, the core panics and
is placed in an endless loop.

Change-Id: Ie393cfe07c7449a2383959e3c968664882e18afc