[llvm] [APInt] Use a std::move() to avoid a copy in the loop in multiplicativeInverse. (PR #87655)

[Eli Friedman via llvm-commits]

efriedma-quic wrote:

> operator*= for APInt still does a new allocation doesn't it?

Umm... yes, I guess.  Maybe we should consider adding `void APInt::mla(const APInt &a, const APInt &b)`, which wouldn't require an allocation.

https://github.com/llvm/llvm-project/pull/87655