ALSA: firewire-lib: leave unit reference counting completely

With previous commit, this module managed to leave the counting to each
drivers, but the isochronous resources functionality still increment/decrement
the count.

This commit purge such codes to leave the responsibility to each drivers.

Fix: c6f224dc20ad ('ALSA: firewire-lib: remove reference counting')
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/firewire/iso-resources.c b/sound/firewire/iso-resources.c
index 5f17b77..f0e4d50 100644
--- a/sound/firewire/iso-resources.c
+++ b/sound/firewire/iso-resources.c
@@ -26,7 +26,7 @@
 int fw_iso_resources_init(struct fw_iso_resources *r, struct fw_unit *unit)
 {
 	r->channels_mask = ~0uLL;
-	r->unit = fw_unit_get(unit);
+	r->unit = unit;
 	mutex_init(&r->mutex);
 	r->allocated = false;
 
@@ -42,7 +42,6 @@
 {
 	WARN_ON(r->allocated);
 	mutex_destroy(&r->mutex);
-	fw_unit_put(r->unit);
 }
 EXPORT_SYMBOL(fw_iso_resources_destroy);