sound: oss: fix uninitialized spinlock

The spinlock lock in sound_timer.c is used without initialization.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/oss/sound_timer.c b/sound/oss/sound_timer.c
index f0f0c19..48cda6c 100644
--- a/sound/oss/sound_timer.c
+++ b/sound/oss/sound_timer.c
@@ -26,7 +26,7 @@
 static volatile unsigned long usecs_per_tmr;	/* Length of the current interval */
 
 static struct sound_lowlev_timer *tmr;
-static spinlock_t lock;
+static DEFINE_SPINLOCK(lock);
 
 static unsigned long tmr2ticks(int tmr_value)
 {