[OVN] Ensure socket files are absent in init_ovn

Just like we remove db files let's also remove
socket files when initializing ovn. Those will
reappear once service fully restarts along with
db files. Without it we see random issue as
described in the below bug.

Closes-Bug: #2002629
Change-Id: I726a9cac9c805d017273aa79e844724f0d00cdf0

lib/neutron_plugins/ovn_agent

@@ -587,6 +587,7 @@ function init_ovn {
     rm -f $OVS_DATADIR/.*.db.~lock~
     sudo rm -f $OVN_DATADIR/*.db
     sudo rm -f $OVN_DATADIR/.*.db.~lock~
+    sudo rm -f $OVN_RUNDIR/*.sock
 }
 
 function _start_ovs {