[SYCL-JIT] Configure VFS explicitly after 866879f (#32766)

Fix assert after 866879f

Fix rtc similar to
clang-tools-extra/clang-include-fixer/IncludeFixer.cpp
and
clang/lib/Tooling/Tooling.cpp

Author: jsji

sycl-jit/jit-compiler/lib/rtc/DeviceCompilation.cpp

@@ -219,6 +219,7 @@ class SYCLToolchain {
       // Create a compiler instance to handle the actual work.
       CompilerInstance Compiler(std::move(Invocation),
                                 std::move(PCHContainerOps));
+      Compiler.setVirtualFileSystem(Files->getVirtualFileSystemPtr());
       Compiler.setFileManager(Files);
       // Suppress summary with number of warnings and errors being printed to
       // stdout.