drm/msm/hdcp1x: add support for HDCP 1.x

Add a module to control the interactions between the Receiver,
Transmitter, and HDCP enforcing hardware layer as part of the
HDCP 1.x protocol. This module is used by DisplayPort interface
driver to initiate HDCP 1.x with a sink and provide a secure
link for content.

This implementation is based on a snapshot of the HDCP 1.x module
as per this commit Ic097e164511 ("msm: mdss: dp: fix HDCP 1.x state
transitions") on kernel-4.4.

CRs-Fixed: 2057884
Change-Id: I1708d64bc659f292356916544bee8ed54d696ca2
Signed-off-by: Tatenda Chipeperekwa <tatendac@codeaurora.org>