[libclc] libclc: Stop requiring SPV_KHR_fma (PR #226186)

[Wenju He via cfe-commits]

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@@ -165,15 +165,14 @@ function(libclc_add_library target_name)
     if(LIBCLC_USE_SPIRV_BACKEND)
       add_custom_command(OUTPUT ${builtins_lib}
         COMMAND ${CMAKE_CLC_COMPILER} -c --target=${ARG_TRIPLE}
-                -mllvm --spirv-ext=+SPV_KHR_fma
+                -mllvm
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wenju-he wrote:

should drop this whole line

https://github.com/llvm/llvm-project/pull/226186