Merge pull request #366 from SgtCoDFish/s390x

re-add support for s390x

Author: cert-manager-prow[bot]

make/00_mod.mk

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+oci_platforms := linux/amd64,linux/arm/v7,linux/arm64,linux/ppc64le,linux/s390x
+
 include make/00_debian_version.mk
 
 repo_name := github.com/cert-manager/trust-manager