arm64, topology: Updates to use DT bindings for EAS costing data

With the bindings and the associated accessors to extract data from the
bindings in place, remove the static hard-coded data from topology.c and
use the accesors instead.

Change-Id: Id2e68b26a5a7b33ec0b3dba8779bf1a2451c4abe
Signed-off-by: Robin Randhawa <robin.randhawa@arm.com>