Merge pull request #1430 from johnelse/clear-platform-flags

Clear out the vGPU platform keys unconditionally
Add helper functions to test_common.ml

Signed-off-by: John Else <john.else@citrix.com>
test bits

Signed-off-by: John Else <john.else@citrix.com>
more stuff!

Signed-off-by: John Else <john.else@citrix.com>