ARM: dts: imx6: set ahb-burst-config as 0 for USB

After setting ahb burst configuration as 0, we can increase tx/rx
burst size, it will improve the USB performance

Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
diff --git a/arch/arm/boot/dts/imx6sx.dtsi b/arch/arm/boot/dts/imx6sx.dtsi
index 167f77b..ea29e2e 100644
--- a/arch/arm/boot/dts/imx6sx.dtsi
+++ b/arch/arm/boot/dts/imx6sx.dtsi
@@ -783,6 +783,7 @@
 				fsl,usbphy = <&usbphy1>;
 				fsl,usbmisc = <&usbmisc 0>;
 				fsl,anatop = <&anatop>;
+				ahb-burst-config = <0x0>;
 				status = "disabled";
 			};
 
@@ -793,6 +794,7 @@
 				clocks = <&clks IMX6SX_CLK_USBOH3>;
 				fsl,usbphy = <&usbphy2>;
 				fsl,usbmisc = <&usbmisc 1>;
+				ahb-burst-config = <0x0>;
 				status = "disabled";
 			};
 
@@ -805,6 +807,7 @@
 				phy_type = "hsic";
 				fsl,anatop = <&anatop>;
 				dr_mode = "host";
+				ahb-burst-config = <0x0>;
 				status = "disabled";
 			};