dfu:usb: Support for g_dnl composite download gadget.

Composite USB download gadget support (g_dnl) for download functions.
This code works on top of composite gadget.

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Vasut <marex@denx.de>
diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile
index 87d1918..2c067c8 100644
--- a/drivers/usb/gadget/Makefile
+++ b/drivers/usb/gadget/Makefile
@@ -29,6 +29,7 @@
 ifdef CONFIG_USB_GADGET
 COBJS-y += epautoconf.o config.o usbstring.o
 COBJS-$(CONFIG_USB_GADGET_S3C_UDC_OTG) += s3c_udc_otg.o
+COBJS-$(CONFIG_USBDOWNLOAD_GADGET) += g_dnl.o
 endif
 ifdef CONFIG_USB_ETHER
 COBJS-y += ether.o epautoconf.o config.o usbstring.o