sh: kfr2r09 board support - LCDC panel

This patch adds support for the WQVGA LCD display used by
the KFR2R09 board. The LCD module is a TX07D34VM0AAA made
by Hitachi, and this module is made up by a R61517 chip
together with a 240x400 pixel display. The screen is
attached to the SuperH Mobile LCDC using a 18-bit SYS bus.

The register settings used by the SYS panel setup code are
based on an out-of-tree driver which apart from duplicating
all LCDC driver code and writing to non-existing hardware
registers also never was posted for upstream merge.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>