sound: oss/sb_audio: cap value in sb201_audio_set_speed()

We set "s" before we have capped "speed" so it could be the wrong value.
This could lead to a divide by zero bug.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/oss/sb_audio.c

@@ -442,7 +442,7 @@ static int sb201_audio_set_speed(int dev, int speed)
 {
 	sb_devc *devc = audio_devs[dev]->devc;
 	int tmp;
-	int s = speed * devc->channels;
+	int s;
 
 	if (speed > 0)
 	{
@@ -452,6 +452,7 @@ static int sb201_audio_set_speed(int dev, int speed)
 			speed = 44100;
 		if (devc->opened & OPEN_READ && speed > 15000)
 			speed = 15000;
+		s = speed * devc->channels;
 		devc->tconst = (256 - ((1000000 + s / 2) / s)) & 0xff;
 		tmp = 256 - devc->tconst;
 		speed = ((1000000 + tmp / 2) / tmp) / devc->channels;