Revert "RootCanal: Use weak_ptr for Phy, Device"

This reverts commit 8e475e84.

Reason for revert: Hangs the emulator

Bug: 227487676
Bug: 241962982
Bug: 242184809
Test: cert/run
Ignore-AOSP-First: Cherry-picked from AOSP
Merged-In: Id6e4630c1f222612a57372f28700a22ac48c37e3
Change-Id: Id6e4630c1f222612a57372f28700a22ac48c37e3