[llvm] [RISCV] Support `llvm.masked.compressstore` intrinsic (PR #83457)

[Kolya Panchenko via llvm-commits]

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nikolaypanchenko wrote:

TTI part of the changeset disallows scalable vectors. The legalization part in `ScalarizeMaskedMemIntrin` cannot handle them either.
It might be better to relax TTI constraint and add tests for scalable vectors in followup patch, what do you think ?

https://github.com/llvm/llvm-project/pull/83457