[device-port][sargo] Google Pixel 3a

[6ninjak]

Tree:

• Create manifest manifests: Adapt to new sargo URLs halium-devices#358
• Boot image and system image build successfully
• Device boots into rootfs, usb: Manufacturer: GNU/Linux Device appears in dmesg on host.
• LXC container starts and does not crash
• libhybris tests
  • test_gps
  • test_hwcomposer
  • test_lights
  • test_vibrator
  • test_wifi
  • test_sensors
  • test_audio
  • test_camera
  • test_input
  • test_nfc
  • test_recorder