dt-bindings: pinctrl: samsung: Document Exynos7885

Document compatible string for Exynos7885 SoC.
Signed-off-by: David Virag <virag.david003@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20211031231511.46856-1-virag.david003@gmail.comSigned-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>

Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt

@@ -22,6 +22,7 @@ Required Properties:
   - "samsung,exynos5420-pinctrl": for Exynos5420 compatible pin-controller.
   - "samsung,exynos5433-pinctrl": for Exynos5433 compatible pin-controller.
   - "samsung,exynos7-pinctrl": for Exynos7 compatible pin-controller.
+  - "samsung,exynos7885-pinctrl": for Exynos7885 compatible pin-controller.
   - "samsung,exynos850-pinctrl": for Exynos850 compatible pin-controller.
   - "samsung,exynosautov9-pinctrl": for ExynosAutov9 compatible pin-controller.