[llvm] [HLSL] Fix Root signature test error (PR #127261)

[Justin Bogner via llvm-commits]

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@@ -155,6 +155,7 @@ analyzeModule(Module &M) {
 
     if (RootElementListNode == nullptr) {
       reportError(Ctx, "Missing Root Element List Metadata node.");
+      continue;
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bogner wrote:

Better to fix this in a separate PR (also are there any tests for this error? I'm surprised they don't crash or otherwise have issues)

https://github.com/llvm/llvm-project/pull/127261