drivers/staging/brcm80211/brcmfmac/wl_iw.c: introduce missing kfree

Error handling code following a kmalloc should free the allocated data.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/brcm80211/brcmfmac/wl_iw.c

@@ -3672,8 +3672,10 @@ int wl_iw_attach(struct net_device *dev, void *dhdp)
 		return -ENOMEM;
 
 	iscan->iscan_ex_params_p = kmalloc(params_size, GFP_KERNEL);
-	if (!iscan->iscan_ex_params_p)
+	if (!iscan->iscan_ex_params_p) {
+		kfree(iscan);
 		return -ENOMEM;
+	}
 	iscan->iscan_ex_param_size = params_size;
 	iscan->sysioc_tsk = NULL;