RootCanal: Reorganize vendor command specification

- rename LeAdvFilter commands to LeApcf
- group vendor command definitions at the end of the hci_packets.pdl file
- remove definitions for android vendor commands and events that are
  not going to be implemented:
  - LE Multi Adv
  - A2DP Hardware Offload
  - Bluetooth Quality Report
- implement stubs for all recognized vendor commands

Bug: 296143555
Test: m root-canal
Change-Id: I294400bc9c03cd0ac5694f8116f82931bfc67cd3