dt-bindings: mmc: mtk-sd: drop assigned-clocks/clock-parents

MT7986 has 2 clock-parents and these properties are not needed in driver
binding. So drop them completely.
Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230629184318.551317-2-linux@fw-web.deSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

Documentation/devicetree/bindings/mmc/mtk-sd.yaml

@@ -91,16 +91,6 @@ properties:
       should switch dat1 pin to GPIO mode.
     maxItems: 1
 
-  assigned-clocks:
-    description:
-      PLL of the source clock.
-    maxItems: 1
-
-  assigned-clock-parents:
-    description:
-      parent of source clock, used for HS400 mode to get 400Mhz source clock.
-    maxItems: 1
-
   hs400-ds-delay:
     $ref: /schemas/types.yaml#/definitions/uint32
     description: