[llvm] [X86] Fix expand-fp on optnone functions (PR #156900)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,98 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -mtriple=x86_64-- --expand-fp < %s | FileCheck %s
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arsenm wrote:

Still means it would be best to also have a codegen test 

https://github.com/llvm/llvm-project/pull/156900