[Bug]: Driver upgrade does not evict pods that use nvidia.com/gpu only in a native sidecar #3026

Describe the bug
During an automatic driver upgrade, the upgrade controller does not delete workload pods whose nvidia.com/gpu resource is declared only in a native sidecar container (an entry in spec.initContainers with restartPolicy: Always).
The GPU pod filter, gpuPodSpecFilter in cmd/gpu-operator/main.go, only iterates pod.Spec.Containers, so such pods are treated as non-GPU pods ("No pods require deletion" logged). They keep the GPU open, k8s-driver-manager cannot unload the driver, the driver pod goes into Init:CrashLoopBackOff and the node ends up in upgrade-failed.

To Reproduce

1. Run a Deployment whose main container has no GPU request, and a native sidecar with one:

  initContainers:
  - name: gpu-sidecar
    restartPolicy: Always
    resources:
      limits: 
        nvidia.com/gpu: 1

2. Change driver.version in the ClusterPolicy.
3. Observe the operator log and the driver pod.

Expected behavior
Pods that declare nvidia.com/gpu* in resources of any container, including native sidecars, are selected by gpuPodSpecFilter and deleted in pod-deletion-required.

Environment (please provide the following information):

• GPU Operator Version: v26.7.1
• OS: Ubuntu24.04
• Kernel Version: 6.17.0-19-generic
• Container Runtime Version: containerd 2.2.6
• Kubernetes Distro and Version: K8s v1.36.1