Add flag to disable hiding complications on touch

The existing logic to hide dream overlay complications on touch is
conflicting with transitions to/from the hub.

Bug: 329091030
Test: "adb shell device_config override systemui
com.android.systemui.remove_dream_overlay_hide_on_touch true" and
verified overlays are no longer hidden on touch
Flag: ACONFIG com.android.systemui.remove_dream_overlay_hide_on_touch DISABLED

Change-Id: I1fca6cc533769e6fb32c54297888f48a2aecf210