ALSA: seq: oss: remove unused inline function snd_seq_oss_timer_is_realtime

There's no callers in-tree.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20200429132805.18712-1-yuehaibing@huawei.comSigned-off-by: Takashi Iwai <tiwai@suse.de>

sound/core/seq/oss/seq_oss_timer.h

@@ -44,14 +44,4 @@ snd_seq_oss_timer_cur_tick(struct seq_oss_timer *timer)
 	return timer->cur_tick;
 }
 
-
-/*
- * is realtime event?
- */
-static inline int
-snd_seq_oss_timer_is_realtime(struct seq_oss_timer *timer)
-{
-	return timer->realtime;
-}
-
 #endif