[XZ3] Display artifacts

[voidanix]

This is a continuation of #150 for 4.5.0.24.

XZ3 still has problems with its display as reported in the aforementioned issue, where artifacts appear when interacting with lipstick.

Although zgovernor was supposed to fix the issue, that is not the case.

out4.getrimmt.mp4

While it is possible to work around this issue by setting the governor to performance inside soc:qcom,gpubw to raise the frequency, kumano at 1144 works perfectly well in comparison (note that kumano uses 1720 by default; akatsuki seems very happy with 1720 too).

This commit might be of interest (along with the relevant changes in techpack), but I sadly do not have a clone of hadk-10 with me to test if it actually does anything in practice.

[rinigus]

As that commit is a part of the kernel, but for newer version, I presume we have to add it to https://github.com/sonyxperiadev/kernel/blob/aosp/LA.UM.7.1.r1/arch/arm64/boot/dts/qcom/dsi-panel-somc-akatsuki.dtsi .

[voidanix]

I presume we have to add it to dsi-panel-somc-akatsuki.dtsi

Indeed, that is where it is supposed to go.

For the record, I just tested this on a janky A11 port and can confirm that the commit of interest fixes the issue: all the SDE code is already included on 4.14 too.

It is probably best to cherry-pick this upstream as well.