[llvm] [CostModel][X86] Add variable divisor div/rem costs for scalar and <=i32 vectors (PR #215124)

[via llvm-commits]

Andarwinux wrote:

I noticed x86 currently doesn't have a cost test for masked divrem like https://github.com/llvm/llvm-project/blob/main/llvm/test/Analysis/CostModel/AArch64/masked-divrem.ll, so might need to add one.

https://github.com/llvm/llvm-project/pull/215124