powerpc/85xx: add aliases for usb nodes on t4240, b4860, and b4420

Add usb aliases for consistency with the other platforms.

Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@freescale.com>
Signed-off-by: Sriram Dash <sriram.dash@nxp.com>
Signed-off-by: Scott Wood <oss@buserror.net>

arch/powerpc/boot/dts/fsl/b4420si-pre.dtsi

@@ -51,6 +51,7 @@
 		serial2 = &serial2;
 		serial3 = &serial3;
 		pci0 = &pci0;
+		usb0 = &usb0;
 		dma0 = &dma0;
 		dma1 = &dma1;
 		sdhc = &sdhc;

arch/powerpc/boot/dts/fsl/b4860si-pre.dtsi

@@ -51,6 +51,7 @@
 		serial2 = &serial2;
 		serial3 = &serial3;
 		pci0 = &pci0;
+		usb0 = &usb0;
 		dma0 = &dma0;
 		dma1 = &dma1;
 		sdhc = &sdhc;

arch/powerpc/boot/dts/fsl/qonverge-usb2-dr-0.dtsi

@@ -32,7 +32,7 @@
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-usb@210000 {
+usb0: usb@210000 {
 	compatible = "fsl-usb2-dr";
 	reg = <0x210000 0x1000>;
 	#address-cells = <1>;

arch/powerpc/boot/dts/fsl/t4240si-pre.dtsi

@@ -56,6 +56,8 @@
 		pci1 = &pci1;
 		pci2 = &pci2;
 		pci3 = &pci3;
+		usb0 = &usb0;
+		usb1 = &usb1;
 		dma0 = &dma0;
 		dma1 = &dma1;
 		dma2 = &dma2;