dt-bindings: sdhci-omap: Add am335x and am437x specific bindings

Add binding for the TI's sdhci-omap controller present in am335x and
am437x devices.
Signed-off-by: Faiz Abbas <faiz_abbas@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20200116105154.7685-9-faiz_abbas@ti.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/sdhci-omap.txt

@@ -7,6 +7,8 @@ For UHS devices which require tuning, the device tree should have a "cpu_thermal
 Required properties:
 - compatible: Should be "ti,dra7-sdhci" for DRA7 and DRA72 controllers
 	      Should be "ti,k2g-sdhci" for K2G
+	      Should be "ti,am335-sdhci" for am335x controllers
+	      Should be "ti,am437-sdhci" for am437x controllers
 - ti,hwmods: Must be "mmc<n>", <n> is controller instance starting 1
 	     (Not required for K2G).
 - pinctrl-names: Should be subset of "default", "hs", "sdr12", "sdr25", "sdr50",