fix vfsub build error

This fix is for the following build error:
kernel-source/fs/aufs/vfsub.c: In function 'vfsub_rename':
kernel-source/fs/aufs/vfsub.c:416:26: error: passing argument 1 of 'vfs_rename'
from incompatible pointer type [-Werror=incompatible-pointer-types]
416 | err = vfs_rename(src_dir, src_dentry, dir, path->dentry,
^~~~~~~
struct inode *

Changed the parameters used when calling vfs_rename() according to:
https://lore.kernel.org/all/20210121131959.646623-14-christian.brauner@ubuntu.com/



Signed-off-by: Jinfeng Wang <jinfeng.wang.cn@windriver.com>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>