dt-bindings: rtc: pcf85063: remove quartz-load-femtofarads restriction for nxp,pcf85063

Original TXT binding doc have not limitition about quartz-load-femtofarads,
which only allow 7000 for nxp,pcf85063.

So remove it to fix below CHECK_DTBS warnings:
arch/arm/boot/dts/nxp/imx/imx6dl-skov-revc-lt2.dtb: rtc@51 (nxp,pcf85063): quartz-load-femtofarads:0: 7000 was expected
from schema $id: http://devicetree.org/schemas/rtc/nxp,pcf85063.yaml#

Signed-off-by: Frank Li <[e-mail]>
Acked-by: Rob Herring (Arm) <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Alexandre Belloni <[e-mail]>

Documentation/devicetree/bindings/rtc/nxp,pcf85063.yaml

···
   - if:
       properties:
         compatible:
-          contains:
-            enum:
-              - nxp,pcf85063
-    then:
-      properties:
-        quartz-load-femtofarads:
-          const: 7000
-  - if:
-      properties:
-        compatible:
           not:
             contains:
               enum: