xenapi - cleanup network configuration

The Xenserver/XCP part of devstack was configuring the hypervisor's
connectivity to the outer world, by adding VLANs, and physical
interfaces to the virtual networks. It added a lot of complexity, and
made it hard to get started with XenServer. This patch removes that
extra complexity, so it is left as an exercise for the user.

Related to blueprint blueprint xenapi-devstack-cleanup

Change-Id: If3367335c3da8621d0afe1f6cae77511fbdbb3e2
diff --git a/tools/xen/xenrc b/tools/xen/xenrc
index e50f954..7aaafd2 100644
--- a/tools/xen/xenrc
+++ b/tools/xen/xenrc
@@ -16,6 +16,16 @@
 OSDOMU_MEM_MB=1024
 OSDOMU_VDI_GB=8
 
+# Network mapping. Specify bridge names or network names. Network names may
+# differ across localised versions of XenServer. If a given bridge/network
+# was not found, a new network will be created with the specified name.
+
+# The management network is specified by the bridge name. xenbr0 is usually
+# the name of the bridge of the network associated with the hypervisor's eth0.
+MGT_BRIDGE_OR_NET_NAME="xenbr0"
+VM_BRIDGE_OR_NET_NAME="OpenStack VM Network"
+PUB_BRIDGE_OR_NET_NAME="OpenStack Public Network"
+
 # VM Password
 GUEST_PASSWORD=${GUEST_PASSWORD:-secrete}
 
@@ -28,28 +38,17 @@
 # Our nova host's network info
 #
 
-# A host-only ip that let's the interface come up, otherwise unused
-VM_IP=${VM_IP:-10.255.255.255}
+# Management network
 MGT_IP=${MGT_IP:-172.16.100.55}
-PUB_IP=${PUB_IP:-192.168.1.55}
+MGT_NETMASK=${MGT_NETMASK:-255.255.255.0}
+
+# VM Network
+VM_IP=${VM_IP:-10.255.255.255}
+VM_NETMASK=${VM_NETMASK:-255.255.255.0}
 
 # Public network
+PUB_IP=${PUB_IP:-192.168.1.55}
 PUB_NETMASK=${PUB_NETMASK:-255.255.255.0}
-PUB_BR=${PUB_BR:-"xenbr0"}
-PUB_VLAN=${PUB_VLAN:--1}
-PUB_DEV=${PUB_DEV:-eth0}
-
-# VM network params
-VM_NETMASK=${VM_NETMASK:-255.255.255.0}
-VM_BR=${VM_BR:-""}
-VM_VLAN=${VM_VLAN:-100}
-VM_DEV=${VM_DEV:-eth0}
-
-# MGMT network params
-MGT_NETMASK=${MGT_NETMASK:-255.255.255.0}
-MGT_BR=${MGT_BR:-""}
-MGT_VLAN=${MGT_VLAN:-101}
-MGT_DEV=${MGT_DEV:-eth0}
 
 # Decide if you should enable eth0,
 # the guest installer network