Staging: hv: vmbus: Change the memory barrier in hv_ringbuffer_write()

Use the correct memory barrier interface in Change the memory barrier
in hv_ringbuffer_write().
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Abhishek Kane <v-abkane@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/ring_buffer.c

@@ -413,7 +413,7 @@ int hv_ringbuffer_write(struct hv_ring_buffer_info *outring_info,
 					     sizeof(u64));
 
 	/* Make sure we flush all writes before updating the writeIndex */
-	mb();
+	smp_wmb();
 
 	/* Now, update the write location */
 	hv_set_next_write_location(outring_info, next_write_location);