Add get_lcd_clk and set_lcd_clk callbacks for Exynos5800 needed by exynos video driver. Signed-off-by: Ajay Kumar <ajaykumar.rs@samsung.com> Reviewed-by: Simon Glass <sjg@chromium.org> Tested-by: Simon Glass <sjg@chromium.org> Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>