remove more unused code

Author: cor3ntin

clang/include/clang/Sema/Sema.h

@@ -14860,8 +14860,6 @@ class Sema final : public SemaBase {
       UnsubstitutedConstraintSatisfactionCache;
 
 private:
-  friend class CalculateConstraintSatisfaction;
-
   /// Caches pairs of template-like decls whose associated constraints were
   /// checked for subsumption and whether or not the first's constraints did in
   /// fact subsume the second's.

clang/include/clang/Sema/SemaConcept.h

@@ -50,13 +50,6 @@ struct NormalizedConstraint {
 
   using OccurenceList = llvm::SmallBitVector;
 
-  friend bool
-  substituteParameterMappings(Sema &S, NormalizedConstraint &N,
-                              const MultiLevelTemplateArgumentList &MLTAL,
-                              const ASTTemplateArgumentListInfo *ArgsAsWritten,
-                              TemplateParameterList *TemplateParams,
-                              const NamedDecl *D);
-
 protected:
   using ExprOrConcept =
       llvm::PointerUnion<const Expr *, const ConceptReference *>;