[AST] Use std::optional in OSLog.cpp (NFC)

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

diff --git a/clang/lib/AST/OSLog.cpp b/clang/lib/AST/OSLog.cpp
index 40fa8c3..5e32041 100644 (file)
--- a/clang/lib/AST/OSLog.cpp
+++ b/clang/lib/AST/OSLog.cpp
@@ -8,6 +8,7 @@
 #include "clang/AST/FormatString.h"
 #include "clang/Basic/Builtins.h"
 #include "llvm/ADT/SmallBitVector.h"
+#include <optional>
 
 using namespace clang;
 
@@ -20,11 +21,11 @@ class OSLogFormatStringHandler
 private:
   struct ArgData {
     const Expr *E = nullptr;
-    Optional<OSLogBufferItem::Kind> Kind;
-    Optional<unsigned> Size;
-    Optional<const Expr *> Count;
-    Optional<const Expr *> Precision;
-    Optional<const Expr *> FieldWidth;
+    std::optional<OSLogBufferItem::Kind> Kind;
+    std::optional<unsigned> Size;
+    std::optional<const Expr *> Count;
+    std::optional<const Expr *> Precision;
+    std::optional<const Expr *> FieldWidth;
     unsigned char Flags = 0;
     StringRef MaskType;
   };