[compiler-rt] Fix extendhfxf2 test (PR #117665)

[Martin Storsjö via llvm-commits]

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@@ -230,7 +230,7 @@ static inline double makeQNaN64(void)
     return fromRep64(0x7ff8000000000000UL);
 }
 
-#if __LDBL_MANT_DIG__ == 64 && defined(__x86_64__)
+#if HAS_80_BIT_LONG_DOUBLE
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mstorsjo wrote:

Previously, we specifically checked for `x86_64` here, but `HAS_80_BIT_LONG_DOUBLE` also is true on i686 mingw, so this will start executing these codepaths on i686 now as well.

https://github.com/llvm/llvm-project/pull/117665