Revert "Revert "DolphinQt: Minor consistency fixes for the Settings window""

This reverts commit e376a985e4.

A beta build has been released now, so there's no reason to keep
it reverted anymore.

Source/Core/DolphinQt/Settings/BroadbandAdapterSettingsDialog.h

@@ -0,0 +1,28 @@
+// Copyright 2021 Dolphin Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <QDialog>
+
+class QLineEdit;
+
+class BroadbandAdapterSettingsDialog final : public QDialog
+{
+  Q_OBJECT
+public:
+  enum class Type
+  {
+    Ethernet,
+    XLinkKai,
+  };
+
+  explicit BroadbandAdapterSettingsDialog(QWidget* target, Type bba_type);
+
+private:
+  QLineEdit* m_address_input;
+  Type m_bba_type;
+
+  void InitControls();
+  void SaveAddress();
+};