include: Add header file with MIPI DSI constants from linux 3.18

The file, originally named "include/video/mipi_display.h", is taken from
linux 3.18 (commit b2776bf7149bddd1f4161f14f79520f17fc1d71d).

It provides MIPI DSI constants for DCS commands, which are needed to
implement support for SSD2828 in u-boot.

Signed-off-by: Siarhei Siamashka <siarhei.siamashka@gmail.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>