dt-bindings: input: iqs7222: Remove support for RF filter

The vendor has marked the RF filter enable control as reserved in
the datasheet; remove it from the binding.

Fixes: 44dc42d2 ("dt-bindings: input: Add bindings for Azoteq IQS7222A/B/C")
Signed-off-by: Jeff LaBundy <jeff@labundy.com>
Link: https://lore.kernel.org/r/20220626072412.475211-8-jeff@labundy.comSigned-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Documentation/devicetree/bindings/input/azoteq,iqs7222.yaml

@@ -37,10 +37,6 @@ properties:
       device is temporarily held in hardware reset prior to initialization if
       this property is present.
 
-  azoteq,rf-filt-enable:
-    type: boolean
-    description: Enables the device's internal RF filter.
-
   azoteq,max-counts:
     $ref: /schemas/types.yaml#/definitions/uint32
     enum: [0, 1, 2, 3]