USB: Change acm_iad_descriptor bFunctionProtocol to USB_CDC_ACM_PROTO_AT_V25TER

The protocol code is set 00 in IAD and it's set to 01 in ACM control
interface descriptor in f_acm.c file. Due to this, windows is unable to
install the modem(ACM) driver based on class-subclass-protocol matching.

This patch corrects the protocol code in ACM IAD to the same as in
acm_control_interface_desc protocol code.

Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Praveena Nadahally <praveen.nadahally@stericsson.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/f_acm.c

@@ -111,7 +111,7 @@ acm_iad_descriptor = {
 	.bInterfaceCount = 	2,	// control + data
 	.bFunctionClass =	USB_CLASS_COMM,
 	.bFunctionSubClass =	USB_CDC_SUBCLASS_ACM,
-	.bFunctionProtocol =	USB_CDC_PROTO_NONE,
+	.bFunctionProtocol =	USB_CDC_ACM_PROTO_AT_V25TER,
 	/* .iFunction =		DYNAMIC */
 };