[lldb][NFC] Remove unused CompilerType::IsPossibleCPlusPlusDynamicType

[teemperor]

(Just leaving this here to have it in my patch queue until the automerger bot is back from the dead).

[davide]

Nice!

lldb/include/lldb/Symbol/CompilerType.h

public:
   bool IsIntegerType(bool &is_signed) const;
 
   bool IsEnumerationType(bool &is_signed) const;
 
   bool IsIntegerOrEnumerationType(bool &is_signed) const;
 
   bool IsPolymorphicClass() const;
 
-  bool
-  IsPossibleCPlusPlusDynamicType(CompilerType *target_type = nullptr) const {
-    return IsPossibleDynamicType(target_type, true, false);
-  }
-
   bool IsPossibleDynamicType(CompilerType *target_type, // Can pass nullptr
                              bool check_cplusplus, bool check_objc) const;
 
   bool IsPointerToScalarType() const;
 
   bool IsRuntimeGeneratedType() const;
 
   bool IsPointerType(CompilerType *pointee_type = nullptr) const;