Any filesystem which is using simple_dir_operations will retunr -EINVAL for
fsync() on a directory.  Make it return zero instead.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
        .llseek         = dcache_dir_lseek,
        .read           = generic_read_dir,
        .readdir        = dcache_readdir,
+       .fsync          = simple_sync_file,
 };
 
 struct inode_operations simple_dir_inode_operations = {