[Merge] ~waveform/ubuntu-seeds/+git/platform:ab_piboot into ~ubuntu-core-dev/ubuntu-seeds/+git/platform:questing

[Dave Jones]

flash-kernel-piboot has now landed in the questing release pocket (thanks to the AA's for the swift review!). Proceeding with updating the seed to include the new package
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https://code.launchpad.net/~waveform/ubuntu-seeds/+git/platform/+merge/488858
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~waveform/ubuntu-seeds/+git/platform:ab_piboot into ~ubuntu-core-dev/ubuntu-seeds/+git/platform:questing.