dt-bindings: mmc: tegra: document Tegra194 compatible string

SDHCI controller of Tegra194 is similar to SDHCI controller in Tegra186.
This patch documents Tegra194 sdhci compatible string.
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/nvidia,tegra20-sdhci.txt

@@ -14,6 +14,7 @@ Required properties:
   - "nvidia,tegra124-sdhci": for Tegra124 and Tegra132
   - "nvidia,tegra210-sdhci": for Tegra210
   - "nvidia,tegra186-sdhci": for Tegra186
+  - "nvidia,tegra194-sdhci": for Tegra194
 - clocks : Must contain one entry, for the module clock.
   See ../clocks/clock-bindings.txt for details.
 - resets : Must contain an entry for each entry in reset-names.