dt-bindings: sdhci-of-at91: add microchip,sam9x7-sdhci

Add microchip,sam9x7-sdhci to DT bindings documentation.
Signed-off-by: Varshini Rajendran <varshini.rajendran@microchip.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20230728102616.266235-1-varshini.rajendran@microchip.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

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

@@ -5,11 +5,13 @@ Documentation/devicetree/bindings/mmc/mmc.txt and the properties used by the
 sdhci-of-at91 driver.
 
 Required properties:
-- compatible:		Must be "atmel,sama5d2-sdhci" or "microchip,sam9x60-sdhci".
+- compatible:		Must be "atmel,sama5d2-sdhci" or "microchip,sam9x60-sdhci"
+			or "microchip,sam9x7-sdhci", "microchip,sam9x60-sdhci".
 - clocks:		Phandlers to the clocks.
 - clock-names:		Must be "hclock", "multclk", "baseclk" for
 			"atmel,sama5d2-sdhci".
 			Must be "hclock", "multclk" for "microchip,sam9x60-sdhci".
+			Must be "hclock", "multclk" for "microchip,sam9x7-sdhci".
 
 Optional properties:
 - assigned-clocks:	The same with "multclk".