drm/panel: simple: Add support for Sharp LQ150X1LG11 panels

The Sharp 15" LQ150X1LG11 panel is an XGA TFT LCD panel.

The simple-panel driver is used to get support for essential
functionality of the panel.

Signed-off-by: Gustaf Lindström <gl@axentia.se>
Signed-off-by: Peter Rosin <peda@axentia.se>
[treding@nvidia.com: change .bpc from 8 to 6]
Signed-off-by: Thierry Reding <treding@nvidia.com>