ALSA: compress: fix the return value for SNDRV_COMPRESS_VERSION

the return value of SNDRV_COMPRESS_VERSION always return default -ENOTTY as the
return value was never updated for this call
assign return value from put_user()

Reported-by: Haynes <hgeorge@codeaurora.org>
CC: stable@vger.kernel.org
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c
index 99db892..9896954 100644
--- a/sound/core/compress_offload.c
+++ b/sound/core/compress_offload.c
@@ -743,7 +743,7 @@
 	mutex_lock(&stream->device->lock);
 	switch (_IOC_NR(cmd)) {
 	case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
-		put_user(SNDRV_COMPRESS_VERSION,
+		retval = put_user(SNDRV_COMPRESS_VERSION,
 				(int __user *)arg) ? -EFAULT : 0;
 		break;
 	case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):