[llvm] Change `fp128` lowering to use `f128` functions by default (PR #76558)

[Ulrich Weigand via llvm-commits]

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@@ -39,7 +39,7 @@ define double @f5(double %x, double %y) {
 
 define fp128 @f6(fp128 %x, fp128 %y) {
 ; CHECK-LABEL: f6:
-; CHECK: brasl %r14, powl at PLT
+; CHECK: brasl %r14, powf128 at PLT
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uweigand wrote:

Why are we seeing all these changes in the SystemZ tests?   On SystemZ we should continue to use the *l names (I thought this is what the `shouldLowerf128AsLongDouble` logic was supposed to achieve?)

https://github.com/llvm/llvm-project/pull/76558