dt-bindings: arm: apple: Add A11 devices

Add the follow apple,t8015 based platforms:

- iPhone 8
- iPhone 8 Plus
- iPhone X

Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Neal Gompa <neal@gompa.dev>
Signed-off-by: Hector Martin <marcan@marcan.st>

Author: asdfugil

Documentation/devicetree/bindings/arm/apple.yaml

@@ -57,6 +57,12 @@ description: |
   - iPad Pro (2nd Generation) (10.5 Inch)
   - iPad Pro (2nd Generation) (12.9 Inch)
 
+  Devices based on the "A11" SoC:
+
+  - iPhone 8
+  - iPhone 8 Plus
+  - iPhone X
+
   Devices based on the "M1" SoC:
 
   - Mac mini (M1, 2020)
@@ -205,6 +211,18 @@ properties:
           - const: apple,t8011
           - const: apple,arm-platform
 
+      - description: Apple A11 SoC based platforms
+        items:
+          - enum:
+              - apple,d20  # iPhone 8 (Global)
+              - apple,d21  # iPhone 8 Plus (Global)
+              - apple,d22  # iPhone X (Global)
+              - apple,d201 # iPhone 8 (GSM)
+              - apple,d211 # iPhone 8 Plus (GSM)
+              - apple,d221 # iPhone X (GSM)
+          - const: apple,t8015
+          - const: apple,arm-platform
+
       - description: Apple M1 SoC based platforms
         items:
           - enum: