arm64: dts: renesas: salvator-common: add dr_mode property for USB2.0 channel 0

Since Salvator-X[S] have a USB2.0 dual-role channel (CN9), this patch
adds dr_mode property for USB2.0 channel 0 (EHCI/OHCI and HS-USB)
as "otg".
Signed-off-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: NSimon Horman <horms+renesas@verge.net.au>

arch/arm64/boot/dts/renesas/salvator-common.dtsi

@@ -272,6 +272,7 @@
 };
 
 &ehci0 {
+	dr_mode = "otg";
 	status = "okay";
 };
 
@@ -284,6 +285,7 @@
 };
 
 &hsusb {
+	dr_mode = "otg";
 	status = "okay";
 };
 
@@ -346,6 +348,7 @@
 };
 
 &ohci0 {
+	dr_mode = "otg";
 	status = "okay";
 };