This also turns off DEBUG_LL, and switches the hardcoded Samsung lowlevel
uart to uart 3 (which is only used to show the "uncompressing kernel"
message at boot, it seems).
Signed-off-by: Olof Johansson <olof@lixom.net> Reviewed-by: Doug Anderson <dianders@chromium.org> Tested-by: Tushar Behera <tushar.behera@linaro.org> Acked-by: Kukjin Kim <kgene.kim@samsung.com>