[llvm] [AArch64] Parameterize repeated FP divisor combine threshold by subtarget (PR #216930)

[Sander de Smalen via llvm-commits]

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@@ -75,28 +77,44 @@ define void @three_fdiv_2xdouble(<2 x double> %D, <2 x double> %a, <2 x double>
   ret void
 }
 
-; Following test cases check we never combine two FDIVs if neither of them
-; calculates a reciprocal.
+; Following test cases check we combine two FDIVs 
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sdesmalen-arm wrote:

nit: (trailing whitespace, also in a few other places)
```suggestion
; Following test cases check we combine two FDIVs
```

https://github.com/llvm/llvm-project/pull/216930