[clang][cli] Port CodeGenOpts simple string flags to new option parsing system

Depends on D84668

Reviewed By: Bigcheese

Original patch by Daniel Grumberg.

Differential Revision: https://reviews.llvm.org/D84669

Author: jansvoboda11

clang/include/clang/Basic/CodeGenOptions.h

@@ -30,6 +30,8 @@ namespace clang {
 /// Bitfields of CodeGenOptions, split out from CodeGenOptions to ensure
 /// that this large collection of bitfields is a trivial class type.
 class CodeGenOptionsBase {
+  friend class CompilerInvocation;
+
 public:
 #define CODEGENOPT(Name, Bits, Default) unsigned Name : Bits;
 #define ENUM_CODEGENOPT(Name, Type, Bits, Default)

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -86,8 +86,6 @@ def err_drv_invalid_thread_model_for_target : Error<
   "invalid thread model '%0' in '%1' for this target">;
 def err_drv_invalid_linker_name : Error<
   "invalid linker name in argument '%0'">;
-def err_drv_invalid_pgo_instrumentor : Error<
-  "invalid PGO instrumentor in argument '%0'">;
 def err_drv_invalid_rtlib_name : Error<
   "invalid runtime library name in argument '%0'">;
 def err_drv_unsupported_rtlib_for_platform : Error<