sound: annotate ->poll() instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/sound/core/init.c b/sound/core/init.c
index 168ae03..8753440 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -344,7 +344,7 @@
 	panic("%s(%p, %p) failed!", __func__, inode, file);
 }
 
-static unsigned int snd_disconnect_poll(struct file * file, poll_table * wait)
+static __poll_t snd_disconnect_poll(struct file * file, poll_table * wait)
 {
 	return POLLERR | POLLNVAL;
 }