[llvm] [UTC][VPlan] Use `-vplan-print-after` for VPlan-dump-based tests (PR #178736)

[Ramkumar Ramachandra via llvm-commits]

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@@ -59,7 +59,11 @@ struct VPlanTransforms {
            any_of(VPlanPrintAfterPasses, [PassName](StringRef Entry) {
              return Regex(Entry).match(PassName);
            }))) {
-        dbgs() << "VPlan after " << PassName << '\n';
+
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artagnon wrote:

Nit: extra newline?

https://github.com/llvm/llvm-project/pull/178736