regulator: rpm-smd-regulator: Add snapshot of rpm-smd-regulator driver

This is snapshot of the rpm-smd-regulator driver as of msm-3.18
'commit 00df358f2e6a ("regulator: rpm-smd-regulator: introduce
BoB regulator type").

Also fix error debug prints used in rpm-smd-regulator driver.

Change-Id: I48c73a97e78f88521bb6dd18fa98c834ffa461de
Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
Signed-off-by: Tirupathi Reddy <tirupath@codeaurora.org>