Use per-display configuration controller for clock dimensions

This makes the clock update its dimensions correctly when the density of
a display changes.
Before this change, it was only working for the default display, as the
configuration controller for the extrnal one was wrong.

Bug: 404242315
Test: PhoneStatusBarViewControllerTest
Flag: com.android.systemui.shared.status_bar_connected_displays
Change-Id: Ibde73a413e24e8410e83612e17d44d0065398e21