USB: gadget: function: fix issue Unneeded variable: "value"

fix below issue reported by coccicheck
drivers/usb/gadget/function/f_eem.c:169:7-12: Unneeded variable:
"value". Return "- EOPNOTSUPP" on line 179

We can not change return type of eem_setup as its registered with callback
function

Signed-off-by: Hariprasad Kelam <hariprasad.kelam@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/gadget/function/f_eem.c

@@ -166,7 +166,6 @@ static struct usb_gadget_strings *eem_strings[] = {
 static int eem_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 {
 	struct usb_composite_dev *cdev = f->config->cdev;
-	int			value = -EOPNOTSUPP;
 	u16			w_index = le16_to_cpu(ctrl->wIndex);
 	u16			w_value = le16_to_cpu(ctrl->wValue);
 	u16			w_length = le16_to_cpu(ctrl->wLength);
@@ -176,7 +175,7 @@ static int eem_setup(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
 		w_value, w_index, w_length);
 
 	/* device either stalls (value < 0) or reports success */
-	return value;
+	return -EOPNOTSUPP;
 }