[readdir] constify ->actor

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c
index 78072e6..293bc2e 100644
--- a/fs/exportfs/expfs.c
+++ b/fs/exportfs/expfs.c
@@ -255,7 +255,11 @@
 	struct inode *dir = path->dentry->d_inode;
 	int error;
 	struct file *file;
-	struct getdents_callback buffer;
+	struct getdents_callback buffer = {
+		.ctx.actor = filldir_one,
+		.name = name,
+		.ino = child->d_inode->i_ino
+	};
 
 	error = -ENOTDIR;
 	if (!dir || !S_ISDIR(dir->i_mode))
@@ -275,11 +279,7 @@
 	if (!file->f_op->iterate)
 		goto out_close;
 
-	buffer.name = name;
-	buffer.ino = child->d_inode->i_ino;
-	buffer.found = 0;
 	buffer.sequence = 0;
-	buffer.ctx.actor = filldir_one;
 	while (1) {
 		int old_seq = buffer.sequence;