[flang] AliasAnalysis: More formally define and distinguish between data and non-data (#91020)

This PR is an implementation for changes proposed in
https://discourse.llvm.org/t/rfc-distinguish-between-data-and-non-data-in-fir-alias-analysis/78759

Test updates were made when the query was on the wrong reference. So, it
is my hope that this will clear ambiguity on the nature of the queries
from here on.
There are also some TODOs that were addressed. 

It also partly implements what
https://github.com/llvm/llvm-project/pull/87723 is attempting to
accomplish. At least, on a point-to-point query between references, the
distinction is made. To apply it to TBAA, would be another PR.

Note that, the changes were minimal in the TBAA code to retain the
current results.