Enable loading of external specializations lazily

Author: vgvassilev

interpreter/llvm-project/clang/include/clang/Driver/Options.td

@@ -2308,7 +2308,7 @@ defm prebuilt_implicit_modules : BoolFOption<"prebuilt-implicit-modules",
   NegFlag<SetFalse>, BothFlags<[NoXarchOption, CC1Option]>>;
 
 defm load_external_specializations_lazily : BoolOption<"f", "load-external-specializations-lazily",
-  LangOpts<"LoadExternalSpecializationsLazily">, DefaultFalse,
+  LangOpts<"LoadExternalSpecializationsLazily">, DefaultTrue,
   PosFlag<SetTrue, [],
           "Load required external specialization only when required.">,
   NegFlag<SetFalse>>,