intel_pmc_ipc: Add Intel Apollo Lake PMC IPC driver

This driver provides support for PMC control on Apollo Lake platforms.
The PMC is an ARC processor which defines some IPC commands for
communication with other entities in the CPU.

Signed-off-by: qipeng.zha <qipeng.zha@intel.com>
[fengguang.wu@intel.com: Fix Sparse and Cocinelle warnings]
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>