[ConstantRange] Add `subWithNoWrap()` method

Summary:
Much like D67339, adds ConstantRange handling for
when we know no-wrap behavior of the `sub`.

Unlike addWithNoWrap(), we only get lucky re returning empty set
for signed wrap. For unsigned, we must perform overflow check manually.

A patch that makes use of this in LVI (CVP) to be posted later.

Reviewers: nikic, shchenz, efriedma

Reviewed By: nikic

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D69918