Fix keyguard on secondary displays

When projecting the display and on keyguard, keyguard
should show the current clock. This code updates the
display manager to be compatible with new clocks.

Also remove the legacy presentation and delete the
associated featureflag.

Fixes: 291289304
Test: atest KeyguardDisplayManagerTest
Test: atest CtsWindowManagerDeviceDisplay:MultiDisplayKeyguardTests
Flag: ACONFIG com.android.systemui.migrate_clocks_to_blueprint
DEVELOPMENT

Change-Id: I9ccb4d04d059b7f374ac781398a113fc17fa570a