message: Fix amalgamated build with multiple .cpp
diff: @@ -22,23 +22,23 @@ namespace duckdb {
  #ifdef _WIN32
  -void *dlopen(const char *file, int mode) {
  +inline void *dlopen(const char *file, int mode) {
  D_ASSERT(file);
  return (void *)LoadLibrary(file);
  }
  -void *dlsym(void *handle, const char *name) {
  +inline void *dlsym(void *handle, const char *name) {
  D_ASSERT(handle);
  return (void *)GetProcAddress((HINSTANCE)handle, name);
  }
  -std::string GetDLError(void) {
  +inline std::string GetDLError(void) {
  return LocalFileSystem::GetLastErrorAsString();
  }
  #else
  -std::string GetDLError(void) {
  +inline std::string GetDLError(void) {
  return dlerror();
  }
  