Fixes test_update_node by testing updated node.
Fixes test_update_node by testing updated node.

Fixes a broken test - test_update_node - by testing the updated node.

Fixes bug #1180143

*ironic/tests/db/test_nodes.py

Change-Id: I402851c58c4f61c600f15960a851f41356240dca

ramineni/myironic,NaohiroTamura/ironic,pshchelo/ironic,NaohiroTamura/ironic,debayanray/ironic_backup,Tehsmash/ironic,bacaldwell/ironic,dims/ironic,citrix-openstack-build/ironic,citrix-openstack-build/ironic,rdo-management/ironic,openstack/ironic,JioCloud/ironic,devananda/ironic,rackerlabs/ironic,ionutbalutoiu/ironic,SauloAislan/ironic,ionutbalutoiu/ironic,hpproliant/ironic,Tan0/ironic,varunarya10/ironic,naterh/ironic,supermari0/ironic,openstack/ironic,froyobin/ironic,faizan-barmawer/openstack_ironic,naototty/vagrant-lxc-ironic,pshchelo/ironic,bacaldwell/ironic,naototty/vagrant-lxc-ironic,redhat-openstack/ironic,SauloAislan/ironic,dims/ironic