dt-bindings: clocks: atmel,at91sam9x5-sckc: add sam9x7

Add bindings for SAM9X7's slow clock controller.

Signed-off-by: Varshini Rajendran <varshini.rajendran@microchip.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Link: https://lore.kernel.org/r/20240729070717.1990654-1-varshini.rajendran@microchip.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>

Author: varshini-rajendran

Documentation/devicetree/bindings/clock/atmel,at91sam9x5-sckc.yaml

@@ -18,7 +18,9 @@ properties:
           - atmel,sama5d4-sckc
           - microchip,sam9x60-sckc
       - items:
-          - const: microchip,sama7g5-sckc
+          - enum:
+              - microchip,sam9x7-sckc
+              - microchip,sama7g5-sckc
           - const: microchip,sam9x60-sckc
 
   reg: