libvirt: removing lxc specific disk mapping

Currently, LXC specific disk mapping is being created, preventing
the attached volumes from being added to the LXC disk mapping.
Removing this part, to allow volumes to be included in mapping.

Related-Bug: #1269990
Change-Id: I97bcff558b6d8876a10adb36c19ab3f4c972a708

nova/tests/virt/libvirt/test_blockinfo.py

@@ -205,6 +205,7 @@ class LibvirtBlockInfoTest(test.TestCase):
         # A simple disk mapping setup, but for lxc
 
         user_context = context.RequestContext(self.user_id, self.project_id)
+        self.test_instance['ephemeral_gb'] = 0
         instance_ref = db.instance_create(user_context, self.test_instance)
 
         mapping = blockinfo.get_disk_mapping("lxc", instance_ref,

nova/virt/libvirt/blockinfo.py

@@ -501,23 +501,6 @@ def get_disk_mapping(virt_type, instance,
         driver.block_device_info_get_mapping(block_device_info))
      if get_device_name(bdm)]
 
-    if virt_type == "lxc":
-        # NOTE(zul): This information is not used by the libvirt driver
-        # however we need to populate mapping so the image can be
-        # created when the instance is started. This can
-        # be removed when we convert LXC to use block devices.
-        root_disk_bus = disk_bus
-        root_device_type = 'disk'
-
-        root_info = get_next_disk_info(mapping,
-                                       root_disk_bus,
-                                       root_device_type,
-                                       boot_index=1)
-        mapping['root'] = root_info
-        mapping['disk'] = root_info
-
-        return mapping
-
     if rescue:
         rescue_info = get_next_disk_info(mapping,
                                          disk_bus, boot_index=1)