MIPS: CPS: Add CM/CPC 3.5 register definitions

Introduce definitions & accessors for a selection of Coherence Manager
(CM) & Cluster Power Controller (CPC) registers that are new with CM
v3.5 & the MIPS I6500. These are primarily registers that will be used
in supporting multiple CPU clusters.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/17006/


Signed-off-by: Ralf Baechle <ralf@linux-mips.org>