test api cleanup: remove unused primitives

[ Mathieu: the rationale for this is that we can always add back that
  code if every needed. Removing leftover GPLv2 test code is an
  incentive to create the appropriate library-wide LGPL/MIT-style
  abstractions.]

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>