[Bug ada/124265] Dimension_System broken for subtypes and components with ranges

[liam at liampwll dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124265

--- Comment #12 from Liam Powell <liam at liampwll dot com> ---
I forgot about array components with range constraints here. Should be trivial
to fix, but I likely won't get around to it today.