[Bug] Cloudwatch datasource with "Assume Role ARN" doesn't work in Openshift

[alrf]

Describe the bug
Getting these logs during Cloudwatch datasource with "Assume Role ARN" configuration in Openshift:

failed to call cloudwatch:ListMetrics: NoCredentialProviders: no valid providers in chain\ncaused by: EnvAccessKeyNotFound: 
failed to find credentials in the environment.\nSharedCredsLoad: failed to load profile, .\nEC2RoleRequestError: 
no EC2 instance role found\ncaused by: RequestError: 
send request failed\ncaused by: Get \"http://169.254.169.254/latest/meta-data/iam/security-credentials/\": 
dial tcp 169.254.169.254:80: connect: connection refused"

169.254.169.254:80 is available from Openshift node, but not from Grafana pod/container.

The problem could probably have been solved using the hostNetwork: true:
https://bugzilla.redhat.com/show_bug.cgi?id=1745720
but there is no option to configure it (or configuration is ignored ?).
e.g. I tried to define it as:

spec:
  deployment:
    securityContext:
      hostNetwork: true

and

spec:
  securityContext:
    hostNetwork: true

The deployment, replicaset, pod were re-deployed, but there was no hostNetwork option.
It looks like the securityContext option is ignored.

Expected behavior
Cloudwatch datasource with "Assume Role ARN" works in Openshift.

Runtime (please complete the following information):

• OS: Linux
• Grafana Operator Version: 3.9.0
• Environment: Openshift in AWS

Additional context
The same configuration (IAM role, grafana-operator, without hostNetwork: true) perfectly works in AWS EKS cluster.

[alrf]

I was able to rebuild operator and fix it.
Added hostNetwork option to deployment configuration.

hostNetwork: true should be used with DNSPolicy: ClusterFirstWithHostNet (pod default DNSPolicy is ClusterFirst)

[HVBE]

Closing, fixed in #380, Thanks for contributing @alrf ! 👍