[Pod] Move Dumpable to be part of SystemUILogLib.

This will let pods be able to depend on Dumpable without depending on
the entirety of SysUI.

Bug: 407513670
Flag: EXEMPT refactor
Test: m SystemUI
Test: dump SysUI -> verify all dumps appear
Change-Id: Ie3c3e97f0c8d9398935f523d73f15b0eba97fbb0