ui: Pull DisplayMap.h from SF

...so it can be used in more places, e.g. libscheduler headers.

Clean up the verbose type for the frontend::DisplayInfo map by aliasing
it as frontend::DisplayInfos.

Bug: 241285475
Fixes: 256881188
Test: Build
Change-Id: Idf36e20ca304190e43618a6cfd7c67e8f62e9d40