fbdev: sh_mobile_hdmi: add support for 1080p modes

Add support for 3 more preprogrammed video modes: 1080p at 24, 50, and 60Hz.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>