[llvm] [Transforms][IndVarSimplify] Add loop no-op elimination to IndVarSimplify (PR #163534)

[Nashe Mncube via llvm-commits]

nasherm wrote:

> This seems like something IndVarSimplify should handle.
@nikic My most recent patch has migrated the work of this patch to IndVarSimplify



https://github.com/llvm/llvm-project/pull/163534