arm: samsung: Remove dead LCD code

Since bb5930d5 ("exynos: video: Convert several boards to driver
model for video") there have been no callers of any of the exynos_lcd_*
family of functions.  Remove these from the boards, and then remove
unused logo and related code as well.

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>