ALSA: echoaudio - Eliminate use after free

Use the call to snd_card_free in the error handling code at the end of the
function, as in the other error cases.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E2;
@@

snd_card_free(E)
...
(
  E = E2
|
* E
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/echoaudio/echoaudio.c

@@ -2184,10 +2184,9 @@ static int __devinit snd_echo_probe(struct pci_dev *pci,
 			goto ctl_error;
 #endif
 
-	if ((err = snd_card_register(card)) < 0) {
-		snd_card_free(card);
+	err = snd_card_register(card);
+	if (err < 0)
 		goto ctl_error;
-	}
 	snd_printk(KERN_INFO "Card registered: %s\n", card->longname);
 
 	pci_set_drvdata(pci, chip);