mmc: tegra: Implement HS400 delay line calibration

Implement HS400 specific delay line calibration procedure. This is a
Tegra specific procedure and has to be performed regardless whether
enhanced strobe or HS400 tuning is used.

Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>