[COMMON] Fix docker-registry-key empty creds

When image repository does not allow anonymous pull, image pull
failed due to empty credentials in docker-registry-key secret.

This change fixes _repository.tpl repository generator to refer to
.global.repositoryCred in override.yaml .

Issue-ID: OOM-2767
Signed-off-by: Satoshi Fujii <fujii-satoshi@jp.fujitsu.com>
Change-Id: I3cd7eabcdda547e99e0461767a0451dc1e51132b
1 file changed