axolotl: retrofit virtual A/B support

This bumps boot control HAL to 1.1, as it is a requirement[1]
for virtual A/B.

Note: This also requires a current bootloader (3.5 and above).

[1] - https://source.android.com/devices/tech/ota/virtual_ab/implement#boot-control-hal



Change-Id: I223428192d0abd6482c4574ced10d111fbabe38d
Signed-off-by: Alexander Martinz <amartinz@shiftphones.com>