Use "= default" for all trivial default ctors and dtors

Replace user-specified empty constructors and destructors with the
compiler-generated versions, which has a number of advantages for code
generation, in addition to being more clear.

Closes #22965.

Closes #24058.

include/wx/addremovectrl.h

@@ -24,8 +24,8 @@ class WXDLLIMPEXP_CORE wxAddRemoveAdaptor
 {
 public:
     // Default ctor and trivial but virtual dtor.
-    wxAddRemoveAdaptor() { }
-    virtual ~wxAddRemoveAdaptor() { }
+    wxAddRemoveAdaptor() = default;
+    virtual ~wxAddRemoveAdaptor() = default;
 
     // Override to return the associated control.
     virtual wxWindow* GetItemsCtrl() const = 0;