msm: mdss: expose mdss tearing check parameters

Tearing may happen for command mode panels when data transfer from mdp
to panel is not synced with panel's own update. These panel dependent
mdp parameters are used by mdp h/w logic to avoid tearing, so they can
be tuned through device tree settings for different panels.

CRs-fixed: 514910
Change-Id: Ibe9e27233692f8e50f36ce3b8be521a4d0097146
Signed-off-by: Huaibin Yang <huaibiny@codeaurora.org>
msm: wb: Ensure iommu reference is available in wb terminate

In static screen case on command mode, when wifi display is
disconnected, buffers don't get free as there is a probability
that iommu is not attached. Ensure that iommu is attached when
wifi display terminate is called.

Signed-off-by: Jeevan Shriram <jshriram@codeaurora.org>

Change-Id: I9f5bb9db3024117da36f0c90af3c9f27ff27873f