drm: Add component-aware simple encoder

This is a simple DRM encoder that gets its connector timings information
from a OF subnode in the device tree and exposes that as a "discovered"
panel. It can be used together with component-based DRM drivers in an
emulated environment where no real encoder or connector hardware exists
and the display output is configured outside the kernel.

Signed-off-by: Tushar Khandelwal <tushar.khandelwal@arm.com>

Upstream-Status: Backport [https://git.linaro.org/landing-teams/working/arm/kernel-release.git/commit/?h=latest-armlt&id=15283f7be4b1e586702551e85b4caf06531ac2fc]
Signed-off-by: Arunachalam Ganapathy <arunachalam.ganapathy@arm.com>

Cherry-pick from https://git.yoctoproject.org/cgit/cgit.cgi/meta-arm/tree/meta-arm-bsp/recipes-kernel/linux/linux-arm64-ack-5.10/tc/0001-drm-Add-component-aware-simple-encoder.patch?h=36e43a3a21282d67c5e010336fd1619f1c6aaac7
Change-Id: I30dc263c093adcc6fb8100ceb7473691f4a01f62
4 jobs for !7 with patch-209402 in 74 minutes and 55 seconds (queued for 2 seconds)
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build-firmware

00:05:44

 
  Build Stage2
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build-android

01:06:59

 
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generate-test

00:02:11

 
  Test
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