arm64: dts: qcom: sdm845-oneplus: Fix speaker GPIO node

Drop the unnecessary mux{} level to make dtbs check happy.
Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230407-topic-msm_dtb-v1-6-6efb4196f51f@linaro.org

arch/arm64/boot/dts/qcom/sdm845-oneplus-common.dtsi

@@ -814,13 +814,11 @@ panel_esd_pin: panel-esd-state {
 	};
 
 	speaker_default: speaker-default-state {
-		mux {
-			pins = "gpio69";
-			function = "gpio";
-			drive-strength = <16>;
-			bias-pull-up;
-			output-high;
-		};
+		pins = "gpio69";
+		function = "gpio";
+		drive-strength = <16>;
+		bias-pull-up;
+		output-high;
 	};
 };