add grenade-dsvm-neutron to integrated gate

this is now passing regularly, and we broke it once with a patch
that wasn't gating on it in devstack. We should have this as part
of the full integrated gate.

Change-Id: I1835cc1068efc4f62e3d1e15ad4d3df9cd24479d
Merge "add grenade-dsvm-neutron to integrated gate"