video: zynqmp: Enable 1024x768 resolution

Add support for 1024x768 60p resolution and set it up this resolution by
default. This resolution is still able to use only one GT line. But for
example 800x600 60p has some issues with settings. That's why extend this
table by tested resolutions.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/957e1e85a05744326ec2606dadc1af6e69976f37.1684312924.git.michal.simek@amd.com

video: zynqmp: Driver for Xilinx ZynqMP DisplayPort Subsystem

The Xilinx ZynqMP SoC has a hardened display pipeline named DisplayPort
Subsystem. It includes a buffer manager, blender, an audio mixer and a
DisplayPort source controller (transmitter). The DisplayPort controller can
source data from memory (non-live input) or the stream (live input). The
DisplayPort controller is responsible for managing the link and physical
layer functionality. The controller packs audio/video data into transfer
units and sends them over the main link. The link rate and lane counts can
be selected based on the application bandwidth requirements. The
DisplayPort pipeline consists of the DisplayPort direct memory access (DMA)
for fetching data from memory. The DisplayPort DMA controller (DPDMA)
supports up to six input channels as non-live input.

This driver supports the DisplayPort Subsystem and implements
1)640x480 resolution
2)RGBA8888 32bpp format
3)DPDMA channel 3 for Graphics
4)Non-live input
5)Fixed 5.4G link rate
6)Tested on ZCU102 board

There will be additional work to configure GT lines based on DT, higher
resolutions, support for more compressed video formats, spliting code to
more files, add support for EDID, audio support, using clock framework for
all clocks and in general code clean up.

Codevelop-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@amd.com>
Signed-off-by: Michal Simek <michal.simek@amd.com>
Link: https://lore.kernel.org/r/5c1567b63d0280dacc7efba2998857c399c25358.1684312924.git.michal.simek@amd.com