ARM: mach-shmobile: add framebuffer support for ap4evb

ap4evb uses an LCD, connected to the SoC over the MIPI bus. This patch adds
platform data to configure this display and a static clock activation.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Tested-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>