usb: gadget: add support for multiple LUNs

Change-Id: I9790007b65a749af2169f3858ffd32a1d616490f
diff --git a/include/linux/usb/android.h b/include/linux/usb/android.h
index 0b11fdaf..e9971f8 100644
--- a/include/linux/usb/android.h
+++ b/include/linux/usb/android.h
@@ -24,6 +24,7 @@
 	u32 swfi_latency;
 	u8 usb_core_id;
 	bool cdrom;
+	int nluns;
 };
 
 #ifndef CONFIG_TARGET_CORE