regulator: cpr3-regulator: add support for configuring CPR IRQ affinity

Add support to configure the CPR interrupt affinity via a CPR3
controller device tree node.  This can be used to avoid servicing
CPR interrupts triggered by a CPU enterring power collapse on the
CPU that just power collapsed.

Change-Id: I4c04a2c255a6bd249c888c0dd0dbda19b8436be2
CRs-Fixed: 949650
Signed-off-by: David Collins <collinsd@codeaurora.org>