feat(cpu): add support for Hunter CPU

This patch adds the basic CPU library code to support the Hunter CPU
in TF-A. This CPU is based on the Makalu core so that library code
was adapted as the basis for this patch.

Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: I956b2dc0f43da7cec3e015252392e2694363e1b3
3 files changed