drivers: thermal: Add support for cpu isolation cooling device

Add support for CPU isolation cooling device driver. CPU Isolation was
part of the CPU cooling device as a last cooling state. This change has
separated the CPU frequency and isolation as separate cooling devices.

This cooling device will register one cooling device per CPU, which can
be used to place isolation mitigation request.

Change-Id: I7f2164e85e2557c07982ecc4316cb6e97793b4d0
Signed-off-by: Ram Chandrasekar <rkumbako@codeaurora.org>