arm64: dts: qcom: sdm850-samsung-w737: correct I2C12 pins drive strength

The pin configuration (done with generic pin controller helpers and
as expressed by bindings) requires children nodes with either:
1. "pins" property and the actual configuration,
2. another set of nodes with above point.

The qup_i2c12_default pin configuration used second method - with a
"pinmux" child.

Fixes: d4b34126 ("arm64: dts: qcom: Add support for Samsung Galaxy Book2")
Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220930192039.240486-2-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/sdm850-samsung-w737.dts

@@ -415,8 +415,10 @@ pinconf {
 };
 
 &qup_i2c12_default {
+	pinmux {
 		drive-strength = <2>;
 		bias-disable;
+	};
 };
 
 &qup_uart6_default {