regulator: cpr3: Configure CPR4 to keep thread vote

Configure CPR4 controller to always keep thread vote
when both HW threads enabled so that the controller
does not consider MID/DN recommendations from other
thread when all sensors mapped to a thread collapsed.

CRs-Fixed: 2233565
Change-Id: I4c6a78b9b7e161da0be9b65bacfc601bde9f5c7a
Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>