Reorganize ORC reader into multiple files and perform some small fixes to cuIO code

cpp/CMakeLists.txt

@@ -1,5 +1,5 @@
 # =============================================================================
-# Copyright (c) 2018-2023, NVIDIA CORPORATION.
+# Copyright (c) 2018-2024, NVIDIA CORPORATION.
 #
 # Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
 # in compliance with the License. You may obtain a copy of the License at
@@ -380,6 +380,8 @@ add_library(
   src/io/orc/dict_enc.cu
   src/io/orc/orc.cpp
   src/io/orc/reader_impl.cu
+  src/io/orc/reader_impl_helpers.cpp
+  src/io/orc/reader_impl_preprocess.cu
   src/io/orc/stats_enc.cu
   src/io/orc/stripe_data.cu
   src/io/orc/stripe_enc.cu

cpp/src/io/orc/aggregate_orc_metadata.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2021-2023, NVIDIA CORPORATION.
+ * Copyright (c) 2021-2024, NVIDIA CORPORATION.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+#pragma once
+
 #include "orc.hpp"
 
 #include <map>