cw1200: Remove useless return variables

This patch remove variables that are initialized with a constant,
are never updated, and are only used as parameter of return.
Return the constant instead of using a variable.

Verified by compilation only.

The coccinelle script that find and fixes this issue is:
// <smpl>
@@
type T;
constant C;
identifier ret;
@@
- T ret = C;
... when != ret
    when strict
return
- ret
+ C
;
// </smpl>

Signed-off-by: Peter Senna Tschudin <[email protected]>
Signed-off-by: John W. Linville <[email protected]>

drivers/net/wireless/cw1200/sta.c

@@ -2289,7 +2289,6 @@ static int cw1200_upload_null(struct cw1200_common *priv)
 
 static int cw1200_upload_qosnull(struct cw1200_common *priv)
 {
-	int ret = 0;
 	/* TODO:  This needs to be implemented
 
 	struct wsm_template_frame frame = {
@@ -2306,7 +2305,7 @@ static int cw1200_upload_qosnull(struct cw1200_common *priv)
 	dev_kfree_skb(frame.skb);
 
 	*/
-	return ret;
+	return 0;
 }
 
 static int cw1200_enable_beaconing(struct cw1200_common *priv,