[llvm] Reenable sched mfma rewrite (PR #180751)

[Matt Arsenault via llvm-commits]

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@@ -101,7 +101,7 @@ static cl::opt<bool> PrintMaxRPRegUsageAfterScheduler(
 
 static cl::opt<bool> DisableRewriteMFMAFormSchedStage(
     "amdgpu-disable-rewrite-mfma-form-sched-stage", cl::Hidden,
-    cl::desc("Disable rewrie mfma rewrite scheduling stage"), cl::init(true));
+    cl::desc("Disable rewrie mfma rewrite scheduling stage"), cl::init(false));
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arsenm wrote:

The flag flip should be done independently of other changes 

https://github.com/llvm/llvm-project/pull/180751