[llvm] [PowerPC] Remove `UnsafeFPMath` uses (PR #154901)

[via llvm-commits]

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@@ -2786,14 +2786,14 @@ def : Pat<(v2f64 (any_frint v2f64:$S)), (v2f64 (XVRDPIC $S))>;
 // Rounding without exceptions (nearbyint). Due to strange tblgen behaviour,
 // these need to be defined after the any_frint versions so ISEL will correctly
 // add the chain to the strict versions.
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paperchalice wrote:

It would be possible when `SDNodeFlags` and `MIFlag` support rounding modes.

https://github.com/llvm/llvm-project/pull/154901