dt-bindings: display/panel: Add Leadtek ltk035c5444t

Add binding for the leadtek ltk035c5444t, which is a 640x480
mipi-dbi over spi / 24-bit RGB panel based on the newvision
NV03052C chipset.

It is found in the Anbernic RG350M mips handheld.

Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220311170240.173846-5-cbranchereau@gmail.com