[llvm] [SandboxVec][DAG] Mark UnscheduledSuccs as invalid when vectorized (PR #185519)

[Jan Patrick Lehr via llvm-commits]

================
@@ -279,7 +288,8 @@ class MemDGNode final : public DGNode {
     assert(PredN != this && "Trying to add a dependency to self!");
     PredN->MemSuccs.insert(this);
     if (!Scheduled) {
-      ++PredN->UnscheduledSuccs;
+      if (!PredN->Scheduled)
+        ++*PredN->UnscheduledSuccs;
----------------
jplehr wrote:

Should this be 
```suggestion
        PredN->incrUnscheduledSuccs();
```
instead?

https://github.com/llvm/llvm-project/pull/185519