Downgrade log level for gone port on status update
Downgrade log level for gone port on status update

If a port is deleted immediately before a status update arrives
from the L2 agent, the port will be missing from the DB. The current
code was logging this at the warning level, but this occurs during
normal operations so it should only be a debug event.

Change-Id: I22af81e6807bfccb4c906ec0873fcbfca67b72df

silenci/neutron,openstack/neutron,swdream/neutron,glove747/liberty-neutron,openstack/neutron,shahbazn/neutron,SamYaple/neutron,vivekanand1101/neutron,javaos74/neutron,adelina-t/neutron,MaximNevrov/neutron,apporc/neutron,dims/neutron,SamYaple/neutron,barnsnake351/neutron,mandeepdhami/neutron,sasukeh/neutron,jacknjzhou/neutron,takeshineshiro/neutron,igor-toga/local-snat,wolverineav/neutron,suneeth51/neutron,mattt416/neutron,dims/neutron,mmnelemane/neutron,bigswitch/neutron,eonpatapon/neutron,skyddv/neutron,vivekanand1101/neutron,yanheven/neutron,javaos74/neutron,sebrandon1/neutron,JianyuWang/neutron,eayunstack/neutron,mandeepdhami/neutron,jumpojoy/neutron,wenhuizhang/neutron,adelina-t/neutron,sebrandon1/neutron,dhanunjaya/neutron,cloudbase/neutron,jumpojoy/neutron,mahak/neutron,bigswitch/neutron,cisco-openstack/neutron,cisco-openstack/neutron,mahak/neutron,watonyweng/neutron,wolverineav/neutron,paninetworks/neutron,yanheven/neutron,skyddv/neutron,wenhuizhang/neutron,glove747/liberty-neutron,dhanunjaya/neutron,apporc/neutron,watonyweng/neutron,silenci/neutron,neoareslinux/neutron,noironetworks/neutron,swdream/neutron,igor-toga/local-snat,mmnelemane/neutron,chitr/neutron,barnsnake351/neutron,eayunstack/neutron,MaximNevrov/neutron,klmitch/neutron,noironetworks/neutron,JianyuWang/neutron,chitr/neutron,shahbazn/neutron,openstack/neutron,asgard-lab/neutron,klmitch/neutron,takeshineshiro/neutron,sasukeh/neutron,mahak/neutron,jacknjzhou/neutron,huntxu/neutron,huntxu/neutron,cloudbase/neutron,neoareslinux/neutron,mattt416/neutron,suneeth51/neutron,paninetworks/neutron,eonpatapon/neutron,asgard-lab/neutron