ALSA: hda/realtek - Fix a wrong condition

sparse complains that "spec->multiout.dac_nids" is a pointer.

sound/pci/hda/patch_realtek.c:2321:37: error: incompatible types for operation (>)
sound/pci/hda/patch_realtek.c:2321:37:    left side has type unsigned short const [usertype] *dac_nids
sound/pci/hda/patch_realtek.c:2321:37:    right side has type int

It was meant to be num_dacs instead of dac_nids.
Although the current code still works as expected (when num_dacs is zero,
dac_nids should be NULL, too), better to fix now, of course.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/patch_realtek.c

@@ -2322,7 +2322,7 @@ static int alc_build_pcms(struct hda_codec *codec)
 		 "%s Analog", codec->chip_name);
 	info->name = spec->stream_name_analog;
 
-	if (spec->multiout.dac_nids > 0) {
+	if (spec->multiout.num_dacs > 0) {
 		p = spec->stream_analog_playback;
 		if (!p)
 			p = &alc_pcm_analog_playback;