efi_loader: correctly render UsbClass DP nodes as text

Correct the text representation of UsbClass device path nodes.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/lib/efi_loader/efi_device_path_to_text.c b/lib/efi_loader/efi_device_path_to_text.c
index 6e27508..b20b7c0 100644
--- a/lib/efi_loader/efi_device_path_to_text.c
+++ b/lib/efi_loader/efi_device_path_to_text.c
@@ -141,7 +141,7 @@
 		struct efi_device_path_usb_class *ucdp =
 			(struct efi_device_path_usb_class *)dp;
 
-		s += sprintf(s, "USBClass(%x,%x,%x,%x,%x)",
+		s += sprintf(s, "UsbClass(0x%x,0x%x,0x%x,0x%x,0x%x)",
 			ucdp->vendor_id, ucdp->product_id,
 			ucdp->device_class, ucdp->device_subclass,
 			ucdp->device_protocol);