[llvm] [RISCV] Don't transfer (select c, t, f) to Zicond when optimizing for size (PR #163501)

[Sam Elliott via llvm-commits]

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lenary wrote:

This eventually calls `Function::hasOptSize()` which will look at the attributes for Os and Oz, so I think both are covered. It would be good to confirm this with a `minsize` test.

https://github.com/llvm/llvm-project/pull/163501