icnss2: Add open loop CPR support

Open loop CPR (core power reduction) is a power save feature that
configs certain voltage for WLAN power rails at runtime. Firmware
will read fuse and calculate the proper voltage and then send it to
CNSS driver. CNSS driver then configs the voltage to WLAN PDC using
TCS command through RPMh. This is to make sure the proper voltage
can be updated during runtime instead just hardcode and vote fixed
value for WLAN power rails.

Change-Id: I631712d0f569a22a7ed7b3ede892f701152ce5f8
Signed-off-by: Naman Padhiar <npadhiar@codeaurora.org>