[llvm] [AMDGPU] expand-fp: Change frem expansion criterion (PR #158285)

[Frederik Harwath via llvm-commits]

frederik-h wrote:

@davemgreen @aemerson @zixu-w @SundeepKushwaha @SixWeining @mandlebug @asb @andreisfr @koachan @kaz7 @RKSimon @uweigand @dschuff I have asked for your review as this PR changes the legalization action for `ISD::FREM` for the targets that you maintain. For some, the cost analysis is affected.

https://github.com/llvm/llvm-project/pull/158285