Add rudimentary handling of alternate settings of USB interfaces - to fix
problems with some USB storage devices. Some code readability improvements.
diff --git a/include/usb.h b/include/usb.h
index 39d7f23..bf71554 100644
--- a/include/usb.h
+++ b/include/usb.h
@@ -108,6 +108,7 @@
 	unsigned char  iInterface;
 
 	unsigned char  no_of_ep;
+	unsigned char  num_altsetting;
 	unsigned char  act_altsetting;
 	struct usb_endpoint_descriptor ep_desc[USB_MAXENDPOINTS];
 } __attribute__ ((packed));