ALSA: ymfpci: Use common error handling code in snd_card_ymfpci_probe()

* Add a jump target so that a bit of exception handling can be better
  reused at the end of this function.

  This issue was detected by using the Coccinelle software.

* The script "checkpatch.pl" pointed information out like the following.

  ERROR: do not use assignment in if condition

  Thus fix a few source code places.

[ This also fixed a potential use-after-free at error path of
  snd_opl3_hwdep_new(), too -- tiwai ]
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/ymfpci/ymfpci.c

@@ -268,10 +268,9 @@ static int snd_card_ymfpci_probe(struct pci_dev *pci,
 	if ((err = snd_ymfpci_create(card, pci,
 				     old_legacy_ctrl,
 			 	     &chip)) < 0) {
-		snd_card_free(card);
 		release_and_free_resource(mpu_res);
 		release_and_free_resource(fm_res);
-		return err;
+		goto free_card;
 	}
 	chip->fm_res = fm_res;
 	chip->mpu_res = mpu_res;
@@ -283,35 +282,31 @@ static int snd_card_ymfpci_probe(struct pci_dev *pci,
 		card->shortname,
 		chip->reg_area_phys,
 		chip->irq);
-	if ((err = snd_ymfpci_pcm(chip, 0)) < 0) {
-		snd_card_free(card);
-		return err;
-	}
-	if ((err = snd_ymfpci_pcm_spdif(chip, 1)) < 0) {
-		snd_card_free(card);
-		return err;
-	}
+	err = snd_ymfpci_pcm(chip, 0);
+	if (err < 0)
+		goto free_card;
+
+	err = snd_ymfpci_pcm_spdif(chip, 1);
+	if (err < 0)
+		goto free_card;
+
 	err = snd_ymfpci_mixer(chip, rear_switch[dev]);
-	if (err < 0) {
-		snd_card_free(card);
-		return err;
-	}
+	if (err < 0)
+		goto free_card;
+
 	if (chip->ac97->ext_id & AC97_EI_SDAC) {
 		err = snd_ymfpci_pcm_4ch(chip, 2);
-		if (err < 0) {
-			snd_card_free(card);
-			return err;
-		}
+		if (err < 0)
+			goto free_card;
+
 		err = snd_ymfpci_pcm2(chip, 3);
-		if (err < 0) {
-			snd_card_free(card);
-			return err;
-		}
-	}
-	if ((err = snd_ymfpci_timer(chip, 0)) < 0) {
-		snd_card_free(card);
-		return err;
+		if (err < 0)
+			goto free_card;
 	}
+	err = snd_ymfpci_timer(chip, 0);
+	if (err < 0)
+		goto free_card;
+
 	if (chip->mpu_res) {
 		if ((err = snd_mpu401_uart_new(card, 0, MPU401_HW_YMFPCI,
 					       mpu_port[dev],
@@ -336,21 +331,24 @@ static int snd_card_ymfpci_probe(struct pci_dev *pci,
 			legacy_ctrl &= ~YMFPCI_LEGACY_FMEN;
 			pci_write_config_word(pci, PCIR_DSXG_LEGACY, legacy_ctrl);
 		} else if ((err = snd_opl3_hwdep_new(opl3, 0, 1, NULL)) < 0) {
-			snd_card_free(card);
 			dev_err(card->dev, "cannot create opl3 hwdep\n");
-			return err;
+			goto free_card;
 		}
 	}
 
 	snd_ymfpci_create_gameport(chip, dev, legacy_ctrl, legacy_ctrl2);
 
-	if ((err = snd_card_register(card)) < 0) {
-		snd_card_free(card);
-		return err;
-	}
+	err = snd_card_register(card);
+	if (err < 0)
+		goto free_card;
+
 	pci_set_drvdata(pci, card);
 	dev++;
 	return 0;
+
+free_card:
+	snd_card_free(card);
+	return err;
 }
 
 static void snd_card_ymfpci_remove(struct pci_dev *pci)