msm: mink: Snapshot of the smcinvoke driver

This patch is a snapshot of smcinvoke driver taken from
msm-4.14 as of commit <c3715e1> (Merge "drm/msm/dp: change
pinctrl configuration to optional").

Change-Id: I5947a61795f8a1122d43530530a69415fa45ddf9
Signed-off-by: Zhen Kong <zkong@codeaurora.org>