[lld] Use std::nullopt instead of None (NFC)

This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

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

1 files changed, 1 insertions, 1 deletions

diff --git a/lld/MinGW/Driver.cpp b/lld/MinGW/Driver.cpp
index 9d41806..ded78ae 100644
--- a/lld/MinGW/Driver.cpp
+++ b/lld/MinGW/Driver.cpp
@@ -116,7 +116,7 @@ static Optional<std::string> findFile(StringRef path1, const Twine &path2) {
   sys::path::append(s, path1, path2);
   if (sys::fs::exists(s))
     return std::string(s);
-  return None;
+  return std::nullopt;
 }
 
 // This is for -lfoo. We'll look for libfoo.dll.a or libfoo.a from search paths.