Daan, please cherry-pick below commit in 4.4-forward into 4.4
commit 8ca8a7217ec155a37b24e3d9cfc3d5fc67adef2d
CLOUDSTACK-6925: [OVS] get rid custom logic to create bridges on hosts
in the XenServer pool for GRE tunnel networks
Fix uses XenServer recommended way
Network.other_config:assume_network_is_shared=true
which ensures bridge is created automatically on hosts in the pool for
GRE tunnel networks. Fix also gets rid of error prone custom logic
that ensures
bridge is created by plugging a VIF into the dom0 and connected to
GRE tunnel network.
