[clang][modules] Don't rely on `std::vector` CTAD (#181182)

clang/lib/Frontend/CompilerInstance.cpp

diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index cb3e6fb..9f1a3c5 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -1998,9 +1998,9 @@
         PPCb->moduleLoadSkipped(Module);
       // Mark the module and its submodules as if they were loaded from a PCM.
       // This prevents emission of the "missing submodule" diagnostic below.
-      std::vector Worklist{Module};
+      std::vector<clang::Module *> Worklist{Module};
       while (!Worklist.empty()) {
-        auto *M = Worklist.back();
+        clang::Module *M = Worklist.back();
         Worklist.pop_back();
         M->IsFromModuleFile = true;
         for (auto *SubM : M->submodules())