sdn: don't blow away all existing CNI plugins or config
sdn: don't blow away all existing CNI plugins or config

The SDN only cares about plugins it runs, which is handled by
explicitly copying known binaries to /host/opt/cni/bin on
daemonset startup; we don't need to remove them all first.

Removing them all would potentially blow away 3rd party CNI
plugins that we shouldn't touch.  Even if they exist, they
won't be activated/used when the SDN daemonset is run due to
the /etc/cni/net.d/ handling.

Also only delete the SDN's config file, otherwise other plugins
like Multus won't be able to work.

Let's play well with others instead of deleting them unconditionally.

aveshagarwal/openshift-ansible,rjhowe/openshift-ansible,ewolinetz/openshift-ansible,tagliateller/openshift-ansible,sdodson/openshift-ansible,jwhonce/openshift-ansible,aveshagarwal/openshift-ansible,liggitt/openshift-ansible,tagliateller/openshift-ansible,sdodson/openshift-ansible,akram/openshift-ansible,kwoodson/openshift-ansible,sdodson/openshift-ansible,aveshagarwal/openshift-ansible,tagliateller/openshift-ansible,markllama/openshift-ansible,aveshagarwal/openshift-ansible,markllama/openshift-ansible,aveshagarwal/openshift-ansible,openshift/openshift-ansible,rjhowe/openshift-ansible,liggitt/openshift-ansible,ewolinetz/openshift-ansible,rjhowe/openshift-ansible,markllama/openshift-ansible,rjhowe/openshift-ansible,kwoodson/openshift-ansible,rhdedgar/openshift-ansible,jwhonce/openshift-ansible,rhdedgar/openshift-ansible,miminar/openshift-ansible,markllama/openshift-ansible,sdodson/openshift-ansible,ewolinetz/openshift-ansible,maxamillion/openshift-ansible,miminar/openshift-ansible,gburges/openshift-ansible,tagliateller/openshift-ansible,miminar/openshift-ansible,liggitt/openshift-ansible,ewolinetz/openshift-ansible,liggitt/openshift-ansible,markllama/openshift-ansible,nak3/openshift-ansible,maxamillion/openshift-ansible,liggitt/openshift-ansible,ewolinetz/openshift-ansible,maxamillion/openshift-ansible,miminar/openshift-ansible,tagliateller/openshift-ansible,gburges/openshift-ansible,jwhonce/openshift-ansible,bparees/openshift-ansible,nak3/openshift-ansible,maxamillion/openshift-ansible,mwoodson/openshift-ansible,jwhonce/openshift-ansible,openshift/openshift-ansible,sdodson/openshift-ansible,jwhonce/openshift-ansible,rjhowe/openshift-ansible,miminar/openshift-ansible,mwoodson/openshift-ansible,akram/openshift-ansible,bparees/openshift-ansible,maxamillion/openshift-ansible