usb:dfu:g_dnl: Change number of exported configurations at composite gadget

USB composite gadget (g_dnl) supports only one configuration. Due to that
the corresponding field - bConfigurationValue has been changed.

Moreover more descriptive names were chosen for relevant fields.

Windows XP setup:
- Thesyscon USB Descriptor Dumper
- zadig_xp program for WinUSB installation (which is required by dfu-util)
- dfu-util for windows (version 0.6)
- TRATS target connected via USB hub to test Win XP machine.

Tested at: Trats - Exynos4210

Signed-off-by: Lukasz Majewski <l.majewski@samsung.com>
Cc: Marek Vasut <marex@denx.de>
Cc: "Egli, Samuel" <samuel.egli@siemens.com>

drivers/usb/gadget/g_dnl.c

@@ -31,8 +31,10 @@
 
 #define STRING_MANUFACTURER 25
 #define STRING_PRODUCT 2
+/* Index of String Descriptor describing this configuration */
 #define STRING_USBDOWN 2
-#define CONFIG_USBDOWNLOADER 2
+/* Number of supported configurations */
+#define CONFIGURATION_NUMBER 1
 
 #define DRIVER_VERSION		"usb_dnl 2.0"
 
@@ -104,7 +106,7 @@ static int g_dnl_config_register(struct usb_composite_dev *cdev)
 	static struct usb_configuration config = {
 		.label = "usb_dnload",
 		.bmAttributes =	USB_CONFIG_ATT_ONE | USB_CONFIG_ATT_SELFPOWER,
-		.bConfigurationValue =	CONFIG_USBDOWNLOADER,
+		.bConfigurationValue =	CONFIGURATION_NUMBER,
 		.iConfiguration =	STRING_USBDOWN,
 
 		.bind = g_dnl_do_config,