arm64: dts: mediatek: mt6795: Add support for display blocks and DPI/DSI

Introduce all nodes for all of the display blocks in the MediaTek Helio
X10 MT6795 SoC, including the DSI PHY and DSI/DPI interfaces: those are
left disabled as usage is board specific.

Reviewed-by: Alexandre Mergnat <amergnat@baylibre.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20230721082822.680010-2-angelogioacchino.delregno@collabora.com


Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>