Remove log decorator deprecated in Liberty
Remove log decorator deprecated in Liberty

log[1] decorator has been deprecated in Liberty and replaced by oslo_log
log_method_call[2] in neutron.

[1] neutron.common.log
[2] oslo_log.helpers

Change-Id: Ia326daaf376865943e93302c45341f7d4fa22d56

asgard-lab/neutron,apporc/neutron,yanheven/neutron,glove747/liberty-neutron,MaximNevrov/neutron,noironetworks/neutron,glove747/liberty-neutron,mahak/neutron,huntxu/neutron,cloudbase/neutron,dims/neutron,mahak/neutron,asgard-lab/neutron,klmitch/neutron,igor-toga/local-snat,jumpojoy/neutron,igor-toga/local-snat,openstack/neutron,huntxu/neutron,dims/neutron,noironetworks/neutron,sebrandon1/neutron,chitr/neutron,jumpojoy/neutron,mahak/neutron,openstack/neutron,yanheven/neutron,cloudbase/neutron,openstack/neutron,MaximNevrov/neutron,klmitch/neutron,eayunstack/neutron,wolverineav/neutron,wolverineav/neutron,eayunstack/neutron,bigswitch/neutron,sebrandon1/neutron,bigswitch/neutron,apporc/neutron,chitr/neutron