arm64: dts: qcom: sm8250-xiaomi-elish: fix USB maximum speed property

Fix typo in USB DWC3 node maximum speed property.

Fixes: a41b6175 ("arm64: dts: qcom: sm8250: Add device tree for Xiaomi Mi Pad 5 Pro")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230304130315.51595-1-krzysztof.kozlowski@linaro.org

arch/arm64/boot/dts/qcom/sm8250-xiaomi-elish.dts

@@ -595,7 +595,7 @@ &usb_1 {
 
 &usb_1_dwc3 {
 	dr_mode = "peripheral";
-	maximum-spped = "high-speed";
+	maximum-speed = "high-speed";
 	/* Remove USB3 phy */
 	phys = <&usb_1_hsphy>;
 	phy-names = "usb2-phy";