[llvm] Assert range attribute is not empty nor full (PR #100601)

[Andreas Jonson via llvm-commits]

andjo403 wrote:

Yes I also started to think about in how may places that needed to have that type of empty/full check to avoid asserts when I looked at that PR, I was not able to think of a case but as you say probably missed some corner case. 
Do you think that if we remove the empty case in the LangRef that we also shall remove the full case feels like that is only an hint to not add ranges that do not add any information. 
so remove this line `The range should not represent the full or empty set. That is, a!=b.`

https://github.com/llvm/llvm-project/pull/100601