aboot: Fix A/B slot success logic

It is enough just to set the success flag for the current slot instead
of touching the retry counter ourselves. The primary bootloader should
do that for us if it sees the success flag.

Also it appears we never actually wrote the flags to disk in the
original commit, so let's do that with attributes_updated variable and
the partition_mark_active_slot function.

Add github CI

Add support for Redmi 6 Pro (xiaomi-sakura)

don't boot from ext2fs boot.img if user requested recovery

Add note that Motorola Moto G5 Plus (potter) can also be used

lk2nd-msm8953: 0.3.1

* Add support for the Fairphone 3
* Fix panel compatible for xiaomi-daisy

xiaomi-vince: Add panel selection and bootloader matching

scripts: Change python scripts to use 'python3' instead

Using `#!/bin/env python` relies on a symlink to python3, which isn't
applied by many distributions.

- Add new supported devices

- Fix KERNEL IS NOT SEANDROID ENFORCING on Samsung devices

Supported devices:
- Motorola Moto G4 Play (harpia)
- Samsung Galaxy A3 (2015) - SM-A300FU
- Samsung Galaxy A5 (2015) - SM-A500FU
- Samsung Galaxy J5 (2016) - SM-J510FN
- Samsung Galaxy S4 Mini Value Edition - GT-I9195I
- Samsung Galaxy Tab A 8.0 LTE (2015) - SM-T357W
- Samsung Galaxy Tab A 9.7 WiFi (2015) - SM-T550
- Wileyfox Swift

Initial Release

Supported devices:
  - Samsung Galaxy A3 (2015) - SM-A300FU
  - Samsung Galaxy A5 (2015) - SM-A500FU
  - Wileyfox Swift