input: add snapshot of qpnp-power-on driver

The qpnp-power-on driver provides support for key presses via
several key specific PMIC inputs.  It also supports reading
power-on reasons and configuring the power-off type (i.e.
restart, shutdown, etc).

This snapshot is taken as of msm-4.14
commit 8397d59b ("input: qpnp-power-on: refactor the
qpnp-power-on driver").

Change-Id: I8105cf74d65609932146157f82a8e99f29a4dde2
Signed-off-by: David Collins <collinsd@codeaurora.org>