V4L/DVB (10125): em28xx: Don't do AC97 vendor detection for i2s audio devices

The current code was trying to query the AC97 registers for the vendor
information even if it was clearly not a AC97 audio device (resulting in errors
in the dmesg output).  This was due to a bug in the way we did the check.
Signed-off-by: Devin Heitmueller <dheitmueller@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/video/em28xx/em28xx-core.c

@@ -497,7 +497,8 @@ int em28xx_audio_setup(struct em28xx *dev)
 		dev->audio_mode.i2s_5rates = 1;
 	}
 
-	if (!(cfg & EM28XX_CHIPCFG_AC97)) {
+	if ((cfg & EM28XX_CHIPCFG_AUDIOMASK) != EM28XX_CHIPCFG_AC97) {
+		/* Skip the code that does AC97 vendor detection */
 		dev->audio_mode.ac97 = EM28XX_NO_AC97;
 		goto init_audio;
 	}