ALSA: hda - Add snd_hda_check_power_state() helper function

... for small refactoring.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 2311114..f82a64d 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -3779,18 +3779,13 @@
 
 	for (i = 0; i < codec->num_nodes; i++, nid++) {
 		unsigned int wcaps = get_wcaps(codec, nid);
-		unsigned int state, target;
+		unsigned int target;
 		if (!(wcaps & AC_WCAP_POWER))
 			continue;
 		target = codec->power_filter(codec, nid, AC_PWRST_D0);
 		if (target == AC_PWRST_D0)
 			continue;
-		state = snd_hda_codec_read(codec, nid, 0,
-					   AC_VERB_GET_POWER_STATE, 0);
-		if (state & AC_PWRST_ERROR)
-			continue;
-		state = (state >> 4) & 0x0f;
-		if (state != target)
+		if (!snd_hda_check_power_state(codec, nid, target))
 			snd_hda_codec_write(codec, nid, 0,
 					    AC_VERB_SET_POWER_STATE, target);
 	}