soc: qcom: Add RPM SMD Driver

This is a snapshot of the RPM-SMD driver functionality as of
'commit 9c23726ad4df ("leds: qpnp-flash: Fix 11
Use-after-free(UAF) for debugfs")' on msm-4.4 branch.

Change-Id: I502300cf26b67679a9344a89b2feaa0dbcc5fb59
Signed-off-by: Raju P.L.S.S.S.N <rplsssn@codeaurora.org>