[DOC] Correct OLM example DeviceConfig namespace to be openshift-amd-gpu

Author: yansun1996

docs/installation/openshift-olm.md

@@ -276,7 +276,7 @@ apiVersion: amd.com/v1alpha1
 kind: DeviceConfig
 metadata:
   name: test-cr
-  namespace: default
+  namespace: openshift-amd-gpu
 spec:
   driver:
     enable: true