Thank you for confirmation :), it's quite important to me that I'm not
only one.
The patch makes `ensure_mount_option_in_fstab.sh`, then rename it to
`include_mount_options_functions.sh`. Alas, this is quite a big patch,
so debbuging it will be cumbersome.
I suspect that problem exists before file is renamed, because there is
`include_mount_options_functions.sh.fix_failing_rules` file that is
empty and `include_mount_options_functions.sh` that should be renamed in
not cleaned buildroot.
Tomorrow I will try to dig deeper (make use of upstream subscription
[sources and OS], then if no solution would be found apply patch bit by
bit).