Handle ntfs-3g EINVAL for attr save/restore

Handle ntfs-3g EINVAL for attr save/restore

It appears that ntfs-3g now returns EINVAL for unsupported ioctls
including FS_IOC_GET_FLAGS and FS_IOC_SET_FLAGS.

Treat EINVAL like the existing expected errors for these calls, but
since there's evidence to suggest that other devices/filesystems use
EINVAL to indicate more serious trouble and use ENOTTY to indicate
unsupported ioctls, include a request to report any occurrences of
EINVAL when ntfs-3g is not involved.

Thanks to Mark J Hewitt for reporting the problem.

Signed-off-by: Rob Browning <rlb@defaultvalue.org>
Tested-by: Rob Browning <rlb@defaultvalue.org>