soc: qcom: add PMIC PON log parser driver

Add a driver which can parse PMIC PON data into a human readable
format.  This log is stored in a binary data structure in PMIC
NVMEM starting with PMIC PMK8350.  It contains PMIC power-on,
power-off, fault, and other information through multiple power-
cycle events.

Change-Id: I5d2d48ba22ed8a6c666581f0730f8350bb722a08
Signed-off-by: David Collins <collinsd@codeaurora.org>