SF: Activate display on boot and fold/unfold

Revert to the behavior before I0d20ce7f7ab3f9e90ef1c72263b8166865486d62
by not activating a display when it transitions from PowerMode::OFF, as
the resulting modeset seems to trigger long waits on some HWCs.

Bug: 261768275
Test: Leader display ID is only logged during boot.
Test: For foldables, leader display ID is also logged on fold/unfold.
Change-Id: I9d2bdd688129880278da336bbc1633857ae29334