Optimise linear strategy access to physical host variables

Change from using variable manager to the var we already have for
the physical host. This saves nearly 50% time for re-running
playbooks/lxc-container-create.yml

Change-Id: Ic50763f9c74746ef94925a4dd52d16e1f313711b

strategy/linear.py

@@ -164,7 +164,7 @@ class StrategyModule(LINEAR.StrategyModule):
                     host=host,
                     caplevel=0
                 )
-                physical_host_vars = self._variable_manager.get_vars(host=ph)
+                physical_host_vars = ph.get_vars()
                 for item in ['ansible_host', 'container_address', 'address']:
                     addr = physical_host_vars.get(item)
                     if addr:

tests/inventory

@@ -7,7 +7,7 @@ container2 container_name=container2
 
 # This is used to test I75f9d0f55ecd875caa1bf608a77c92f950b679a1
 [hosts]
-localhost_alt
+localhost_alt ansible_host=127.0.0.1
 [all_containers]
 container3 container_name=container3