qti: Add SPMI PMIC arbitrator driver

This patch adds a very rudimentary driver for the SPMI arbitrator used
to access the PMIC. It doesn't support all the controller's actual
arbitration features, so it should probably not be used concurrently
with a running kernel (and it's also not optimized for performance). But
it can be used to set a few registers during boot or on shutdown to
control reset handling, which is all we need it for.

Change-Id: I8631c34a2a89ac71aa1ec9b8266e818c922fe34a
Signed-off-by: Julius Werner <jwerner@chromium.org>
2 files changed