Try and restore the lowcode capability to return int64 result on various 32bits ABI.
The ABIResultRegHigh needs to be defined.
*** Hack ***
Do not entirely take the regenerated lowcode source from VMMaker.oscog-nice.2709.
As there are other changes pending, this may break something else.
Instead, just cherry pick the minimal change from the generated code with the goal to let CI pass.
We could obtain the exact same result by patching VMMaker.oscog-eem.2705, but this is overkill for a temporary.