ARM: Add support for the display controllers in VT8500 and WM8505

This adds drivers for the LCD controller found in VIA VT8500 SoC,
GOVR display controller found in WonderMedia WM8505 SoC and for the
Graphics Engine present in both of them that provides hardware
accelerated raster operations (used for copyarea and fillrect).

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>