arm: dts: mt8183: Move pinfunc to include/dt-bindings/pinctrl

Move mt8183-pinfunc.h into include/dt-bindings/pinctrl so that we can
include it in yaml examples.
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Link: https://lore.kernel.org/r/20210804044033.3047296-2-hsinyi@chromium.orgSigned-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm64/boot/dts/mediatek/mt8183.dtsi

@@ -14,7 +14,7 @@
 #include <dt-bindings/reset-controller/mt8183-resets.h>
 #include <dt-bindings/phy/phy.h>
 #include <dt-bindings/thermal/thermal.h>
-#include "mt8183-pinfunc.h"
+#include <dt-bindings/pinctrl/mt8183-pinfunc.h>
 
 / {
 	compatible = "mediatek,mt8183";