RootCanal: Rewrite LE connection logic

Specifically the checks run by the initiator before sending a
connect indication to a connectable advertising PDU.

Bug: 245578454
Test: gdcert + pts-bot
Ignore-AOSP-First: Cherry-picked from AOSP
Merged-In: I759cbde63505528b9ba296835a542b40b0c425c4
Change-Id: I759cbde63505528b9ba296835a542b40b0c425c4