ISDN HiSax: uninitialized return in hisax_cs_setup

Coverity (1792) spotted a possibly uninitialized return value in case of
kmalloc() failure:

1116 static int hisax_cs_setup(int cardnr, struct IsdnCard *card,
1117                           struct IsdnCardState *cs)
1119         int ret;
1120
1121         if (!(cs->rcvbuf = kmalloc(MAX_DFRAME_LEN_L1, GFP_ATOMIC))) {
1122                 printk(KERN_WARNING "HiSax: No memory for isac rcvbuf\n");
1123                 ll_unload(cs);
1124                 goto outf_cs;
...
1165 outf_cs:
1166         kfree(cs);
1167         card->cs = NULL;
1168         return ret;

The straightforward solution would be to just add the missing
initialization but hardcoding the return value in the out_cs branch
(only taken on failure) seems to work just as well and it allows killing
a couple of other lines too.

Signed-off-by: Florin Malita <fmalita@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>