[DWARF] Inheritance `DW_TAG`s dropped by GC

[SingleAccretion]

Reproduction:
1) Compile the following C++ to WASM with -g:

struct Base { int BaseValue; };
struct Derived : public Base { int DerivedValue; };

int main()
{
    Derived x;
    x.BaseValue = 2;
    x.DerivedValue = 1;
    return 0;
}

2) Run under wasmtime+LLDB:

> lldb wasmtime -Ddebug-info -Oopt-level=0 main.wasm
> (lldb) b main
> (lldb) ...
> (lldb) v x.BaseValue

Expected result:

(int) x.BaseValue = 1

Actual result:

error: "BaseValue" is not a member of "(Derived) x"

Cause: DI GC drops correctness-bearing DW_TAG_inheritance DIEs.

Fix incoming...