regulator: rpm-smd: Send the logical mode instead of the raw mode

RPM PMIC driver expects logical mode values for PMIC4 targets
instead of raw mode. Fix the same.

Change-Id: I8242dd76159f0d9e0169f49622827f55ce6665dd
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>