ALSA: core: timer: remove redundant assignment

Cppcheck complains about a possible NULL pointer dereference but it
actually looks like the NULL assignment is not needed (same loop is
used in other parts of the file without it).
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200902212133.30964-5-pierre-louis.bossart@linux.intel.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/timer.c

@@ -173,7 +173,7 @@ EXPORT_SYMBOL(snd_timer_instance_free);
  */
 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 {
-	struct snd_timer *timer = NULL;
+	struct snd_timer *timer;
 
 	list_for_each_entry(timer, &snd_timer_list, device_list) {
 		if (timer->tmr_class != tid->dev_class)