drm/panel: simple: Add DLC DLC0700YZG-1 panel

This patch adds support for DLC DLC0700YZG-1 1024x600 LVDS panels
to the simple-panel driver.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
[m.felsch@pengutronix.de: fix typo in compatible dt-binding]
[m.felsch@pengutronix.de: add property bindings]
Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180523092504.5142-3-m.felsch@pengutronix.de