mmc: tegra: Configure default trim value on reset

Program the outbound sampling trim value in tegra_sdhci_reset(). Unlike
the outbound tap value this does not depend on the signaling mode and
needs to be only programmed once.

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