Fix Flang build

Author: jansvoboda11

flang/lib/Frontend/FrontendActions.cpp

@@ -936,20 +936,18 @@ void CodeGenAction::runOptimizationPipeline(llvm::raw_pwrite_stream &os) {
     pgoOpt = llvm::PGOOptions(opts.InstrProfileOutput.empty()
                                   ? llvm::driver::getDefaultProfileGenName()
                                   : opts.InstrProfileOutput,
-                              "", "", opts.MemoryProfileUsePath, nullptr,
+                              "", "", opts.MemoryProfileUsePath,
                               llvm::PGOOptions::IRInstr,
                               llvm::PGOOptions::NoCSAction,
                               llvm::PGOOptions::ColdFuncOpt::Default, false,
                               /*PseudoProbeForProfiling=*/false, false);
   } else if (opts.hasProfileIRUse()) {
-    llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
-        llvm::vfs::getRealFileSystem();
     // -fprofile-use.
     auto CSAction = opts.hasProfileCSIRUse() ? llvm::PGOOptions::CSIRUse
                                              : llvm::PGOOptions::NoCSAction;
     pgoOpt = llvm::PGOOptions(
         opts.ProfileInstrumentUsePath, "", opts.ProfileRemappingFile,
-        opts.MemoryProfileUsePath, VFS, llvm::PGOOptions::IRUse, CSAction,
+        opts.MemoryProfileUsePath, llvm::PGOOptions::IRUse, CSAction,
         llvm::PGOOptions::ColdFuncOpt::Default, false);
   }