Add a simple device tree probe support for mxsfb driver. Before
a common binding for struct fb_videomode is available, the driver will
keep using struct mxsfb_platform_data. That said, platform code will
use auxdata to attach mxsfb_platform_data for device tree boot.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Shawn Guo