[ALSA] Add snd_pcm_group_for_each_entry() for code cleanup

Added a new macro snd_pcm_group_for_each_entry() just for code cleanup.
Old macros, snd_pcm_group_for_each() and snd_pcm_group_substream_entry(),
are removed.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
diff --git a/sound/pci/trident/trident_main.c b/sound/pci/trident/trident_main.c
index 3bff321..7ca6062 100644
--- a/sound/pci/trident/trident_main.c
+++ b/sound/pci/trident/trident_main.c
@@ -1540,7 +1540,6 @@
 				    
 {
 	struct snd_trident *trident = snd_pcm_substream_chip(substream);
-	struct list_head *pos;
 	struct snd_pcm_substream *s;
 	unsigned int what, whati, capture_flag, spdif_flag;
 	struct snd_trident_voice *voice, *evoice;
@@ -1563,8 +1562,7 @@
 	what = whati = capture_flag = spdif_flag = 0;
 	spin_lock(&trident->reg_lock);
 	val = inl(TRID_REG(trident, T4D_STIMER)) & 0x00ffffff;
-	snd_pcm_group_for_each(pos, substream) {
-		s = snd_pcm_group_substream_entry(pos);
+	snd_pcm_group_for_each_entry(s, substream) {
 		if ((struct snd_trident *) snd_pcm_substream_chip(s) == trident) {
 			voice = s->runtime->private_data;
 			evoice = voice->extra;