drm/panel: simple: Add Logic PD Type 28 display support

Previously, there was an omap panel-dpi driver that would
read generic timings from the device tree and set the display
timing accordingly.  This driver was removed so the screen
no longer functions.  This patch modifies the panel-simple
file to setup the timings to the same values previously used.

Fixes: 8bf4b162 ("drm/omap: Remove panel-dpi driver")

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191016135147.7743-1-aford173@gmail.com