dt-bindings: display: Add bindings for the LeMaker BL035-RGB-002 LCD panel

This adds the device-tree bindings for the LeMaker BL035-RGB-002 3.5"
QVGA TFT LCD panel, compatible with simple-panel.

Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181107181843.27628-6-contact@paulk.fr