Add lowering TODO for bindings returning derived types or arrays

Codegen does not support fir.addressof of functions returning derived
types, arrays are descriptors inside GlobalOp region.

This is because the  abstract-result-opt is required to rewrite such
functions (a hidden argument must be added), but this pass is meant to
run in GlobalOp currently.

Such fir.address_of may be created when lowering procedure pointers
initial value (TODO), or when creating derived type descriptors for
types with bindings.

Add a TODO in lowering until abstract-result-opt is modified to run
on GlobalOp too.

This patch is part of the upstreaming effort from fir-dev branch.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D127722