ALSA: mixart: silence unitialized variable warnings

We print can print the uninitialized memory on error.  Which is an info
leak, I suppose but it's basically harmless.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/mixart/mixart_mixer.c

@@ -726,7 +726,7 @@ int mixart_update_playback_stream_level(struct snd_mixart* chip, int is_aes, int
 	int volume[2];
 	struct mixart_msg request;
 	struct mixart_set_out_stream_level_req set_level;
-	u32 status;
+	u32 status = 0;
 	struct mixart_pipe *pipe;
 
 	memset(&set_level, 0, sizeof(set_level));
@@ -778,7 +778,7 @@ int mixart_update_capture_stream_level(struct snd_mixart* chip, int is_aes)
 	struct mixart_pipe *pipe;
 	struct mixart_msg request;
 	struct mixart_set_in_audio_level_req set_level;
-	u32 status;
+	u32 status = 0;
 
 	if(is_aes) {
 		idx = 1;