The imx6q/dl supports SDR50 tunning, enable it for a better timing
on SDR50 mode.
Signed-off-by: NDong Aisheng <b29396@freescale.com>
Acked-by: NShawn Guo <shawn.guo@linaro.org>
Signed-off-by: NChris Ball <cjb@laptop.org>