Bug#925966: autopkgtest-buildvm-ubuntu-cloud: restore support for precise, trusty

[Martin Pitt]

Control: tag -1 pending

Hello Dan,

Dan Streetman [2019-03-29 10:48 -0400]:
>   * autopkgtest-buildvm-ubuntu-cloud: work with precise and trusty;
>     they aren't dead yet!
>     (LP: #1822331)

Thanks! Committed.

Martin