Allow override of istiod-tls certificate common name in helm chert (for non-standard istiod deployments)

[SpectralHiss]

Hello

The current istio-csr helm chart deploys the istiod-tls serving certificate as a cert-manager Certificate object at installation,
As you can see in link, the common name is statically set to: istiod.istio-system.svc.

In certain installations like Openshift, this will not be the correct address for Istiod as the Redhat Service Mesh operator appends the revision name to the service name for Pilot.
If we could add a parameter to override this default it would be important for this use-case and perhaps other scenarios also.

[kuberkaul]

+1