[mlir] Remove remaining uses of llvm::Optional (NFC)

This patch removes one "using" declaration and #include
"llvm/ADT/Optional.h".  It keeps several "using" declarations in
headers for downstream users.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716

Author: kazutakahirata

mlir/examples/toy/Ch1/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch2/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch3/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch4/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch5/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch6/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/examples/toy/Ch7/include/toy/Parser.h

@@ -17,7 +17,6 @@
 #include "toy/AST.h"
 #include "toy/Lexer.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/StringExtras.h"
 #include "llvm/Support/raw_ostream.h"

mlir/include/mlir/Analysis/Presburger/Simplex.h

@@ -22,7 +22,6 @@
 #include "mlir/Analysis/Presburger/Utils.h"
 #include "mlir/Support/LogicalResult.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/StringSaver.h"

mlir/include/mlir/Bindings/Python/PybindAdaptors.h

@@ -25,7 +25,6 @@
 #include "mlir-c/Bindings/Python/Interop.h"
 #include "mlir-c/IR.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/Twine.h"
 
 namespace py = pybind11;

mlir/include/mlir/Dialect/Affine/Analysis/AffineAnalysis.h

@@ -17,7 +17,6 @@
 
 #include "mlir/Dialect/Arith/IR/Arith.h"
 #include "mlir/IR/Value.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include <optional>
 

mlir/include/mlir/Dialect/Affine/Analysis/LoopAnalysis.h

@@ -15,7 +15,6 @@
 
 #include "mlir/Support/LLVM.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include <optional>
 
 namespace mlir {

mlir/include/mlir/ExecutionEngine/MemRefUtils.h

@@ -17,7 +17,6 @@
 #include "mlir/ExecutionEngine/CRunnerUtils.h"
 #include "mlir/Support/LLVM.h"
 #include "llvm/ADT/ArrayRef.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/STLExtras.h"
 
 #include "llvm/Support/raw_ostream.h"

mlir/include/mlir/Pass/PassManager.h

@@ -13,7 +13,6 @@
 #include "mlir/IR/OperationSupport.h"
 #include "mlir/Support/LogicalResult.h"
 #include "mlir/Support/Timing.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/Support/raw_ostream.h"

mlir/include/mlir/Support/LogicalResult.h

@@ -10,7 +10,6 @@
 #define MLIR_SUPPORT_LOGICALRESULT_H
 
 #include "mlir/Support/LLVM.h"
-#include "llvm/ADT/Optional.h"
 #include <optional>
 
 namespace mlir {

mlir/lib/Analysis/Presburger/Simplex.cpp

@@ -9,7 +9,6 @@
 #include "mlir/Analysis/Presburger/Simplex.h"
 #include "mlir/Analysis/Presburger/Matrix.h"
 #include "mlir/Support/MathExtras.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/Support/Compiler.h"
 #include <numeric>
 #include <optional>

mlir/lib/AsmParser/Token.h

@@ -10,7 +10,6 @@
 #define MLIR_LIB_PARSER_TOKEN_H
 
 #include "mlir/Support/LLVM.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/SMLoc.h"
 #include <optional>

mlir/lib/Bindings/Python/Globals.h

@@ -15,7 +15,6 @@
 
 #include "PybindUtils.h"
 
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/ADT/StringSet.h"
 

mlir/lib/Bindings/Python/IRAttributes.cpp

@@ -20,7 +20,6 @@ namespace py = pybind11;
 using namespace mlir;
 using namespace mlir::python;
 
-using llvm::Optional;
 using llvm::SmallVector;
 using llvm::Twine;
 

mlir/lib/Bindings/Python/IRModule.h

@@ -21,7 +21,6 @@
 #include "mlir-c/IR.h"
 #include "mlir-c/IntegerSet.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/Optional.h"
 
 namespace mlir {
 namespace python {

mlir/lib/Bindings/Python/PybindUtils.h

@@ -10,7 +10,6 @@
 #define MLIR_BINDINGS_PYTHON_PYBINDUTILS_H
 
 #include "mlir-c/Support.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/Support/DataTypes.h"
 

mlir/lib/Tools/lsp-server-support/Protocol.h

@@ -24,7 +24,6 @@
 #define LIB_MLIR_TOOLS_LSPSERVERSUPPORT_PROTOCOL_H_
 
 #include "mlir/Support/LLVM.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/Support/JSON.h"
 #include "llvm/Support/SourceMgr.h"
 #include "llvm/Support/raw_ostream.h"

mlir/tools/mlir-linalg-ods-gen/mlir-linalg-ods-yaml-gen.cpp

@@ -20,7 +20,6 @@
 #include "mlir/IR/MLIRContext.h"
 #include "mlir/Support/FileUtilities.h"
 #include "mlir/Support/LLVM.h"
-#include "llvm/ADT/Optional.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"