linux-imx

mmc: sdhci: Export sdhci tuning function symbol

Export sdhci tuning function symbols which are used by other SD Host
controller driver modules.

Signed-off-by: ernest.zhang <ernest.zhang@bayhubtech.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>