Show the Tangor Unseen Notification Toggle when notification_minimalism is Enabled

Show the Tangor unseen notification toggle in the Notification settings when
notification_minimalism flag is enabled on both phones and large screen devices.

Bug: 330387368
Bug: 354047572
Flag: com.android.server.notification.notification_minimalism
Test: atest ShowOnlyUnseenNotificationsOnLockscreenPreferenceControllerTest
Change-Id: Ic126b7885eb29897b55c4acdc1a2f73b4bc7841e