drivers/isdn: 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,l;
position p1,p2;
expression *ptr != NULL;
@@

(
if ((x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...)) == NULL) S
|
x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
)
<... when != x
     when != if (...) { <+...x...+> }
x->f = E
...>
(
 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: NJulia Lawall <julia@diku.dk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/isdn/hardware/mISDN/hfcmulti.c

@@ -4599,6 +4599,7 @@ init_e1_port(struct hfc_multi *hc, struct hm_map *m)
 			printk(KERN_ERR "%s: no memory for coeffs\n",
 			    __func__);
 			ret = -ENOMEM;
+			kfree(bch);
 			goto free_chan;
 		}
 		bch->nr = ch;
@@ -4767,6 +4768,7 @@ init_multi_port(struct hfc_multi *hc, int pt)
 			printk(KERN_ERR "%s: no memory for coeffs\n",
 			    __func__);
 			ret = -ENOMEM;
+			kfree(bch);
 			goto free_chan;
 		}
 		bch->nr = ch + 1;