Fix more redundant declarations

... introduced with merge of smart_holder branch

Author: rhaschke

include/pybind11/detail/function_record_pyobject.h

@@ -173,9 +173,6 @@ inline int tp_init_impl(PyObject *, PyObject *, PyObject *) {
     // return -1; // Unreachable.
 }
 
-// The implementation needs the definition of `class cpp_function`.
-void tp_dealloc_impl(PyObject *self);
-
 inline void tp_free_impl(void *) {
     pybind11_fail("UNEXPECTED CALL OF function_record_PyTypeObject_methods::tp_free_impl");
 }

include/pybind11/detail/type_caster_base.h

@@ -511,9 +511,14 @@ inline PyThreadState *get_thread_state_unchecked() {
 void keep_alive_impl(handle nurse, handle patient);
 inline PyObject *make_new_instance(PyTypeObject *type);
 
+PYBIND11_WARNING_PUSH
+PYBIND11_WARNING_DISABLE_GCC("-Wredundant-decls")
+
 // PYBIND11:REMINDER: Needs refactoring of existing pybind11 code.
 inline bool deregister_instance(instance *self, void *valptr, const type_info *tinfo);
 
+PYBIND11_WARNING_POP
+
 PYBIND11_NAMESPACE_BEGIN(smart_holder_type_caster_support)
 
 struct value_and_holder_helper {