dm: usb: tegra: Drop legacy USB code

Drop the code that doesn't use driver model for USB.

Signed-off-by: Simon Glass <sjg@chromium.org>

arch/arm/mach-tegra/board2.c

@@ -161,9 +161,6 @@ int board_init(void)
 
 #ifdef CONFIG_USB_EHCI_TEGRA
 	pin_mux_usb();
-# ifndef CONFIG_DM_USB
-	usb_process_devicetree(gd->fdt_blob);
-# endif
 #endif
 
 #ifdef CONFIG_LCD