caroline-chrome-pfq has recently started to fail in VMTests:
https://luci-milo.appspot.com/buildbot/chromeos/betty-chrome-pfq/

We should only run VMTests for betty* boards (Issue 710629), and with the recent removal of support for cirrus boards not running kernel 4.4 are expected to fail VMTests soon anyway.

We should remove VMTests from all Chrome PFQ builders that aren't specifically meant to be VMs. AFAICT some PFQ builders skip VMTests, some don't instantiate them at all, we should clean up all of them.