Respect partition precedence while deciding overlay priority

Strict partition precedence is enforced now, and the legacy
android:priority is no longer able to reorder overlays across
partition boundaries.

Should use OverlayConfig instead to do the custom configuration
if a cross partition reorder is needed.

Bug: 254407173
Test: atest OverlayConfigTest
Change-Id: I915957bee2ce00286c1bad853206e7e5cb1d140b