Looks like quite a few omap3 boards have sharp ls037v7dw01 that's
configured as various panel dpi entries for whatever legacy reasons.
For device tree based support, let's just configure these properly for
panel ls037v7dw01 instead of panel dpi.

This patch creates a common file for panel ls037v7dw01, and makes
boards ldp and omap3-evm to use it.

The ls037v7dw01 also seems to be coupled with an ad7846 touchscreen
controller for the omaps, so let's add a basic configuration for
the touchscreen also using the default values.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>