fs: Fix description of vfs_tmpfile()

Update the description of vfs_tmpfile() to match the current parameters of
that function.

Fixes: 9751b33 ("vfs: move open right after ->tmpfile()")
Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Author: robertosassu

fs/namei.c

@@ -3574,9 +3574,9 @@ static int do_open(struct nameidata *nd,
 /**
  * vfs_tmpfile - create tmpfile
  * @idmap:	idmap of the mount the inode was found from
- * @dentry:	pointer to dentry of the base directory
+ * @parentpath:	pointer to the path of the base directory
+ * @file:	file descriptor of the new tmpfile
  * @mode:	mode of the new tmpfile
- * @open_flag:	flags
  *
  * Create a temporary file.
  *