This adds context to all the relevant cloud provider interface signatures.
Callers of those APIs are currently satisfied using context.TODO().
There will be follow on PRs to push the context through the stack.
For an idea of the full scope of this change please look at PR #58532.
This change is prerequisite for implementing iSCSI attacher
and detacher.
In order to use chap authentication at iSCSI plugin after
implementing attacher and detacher, secret is needed at
AttachDisk() which is called from WaitForAttach().
To obtain secret, pod information is required, but
WaitForAttach() doesn't pass pod information inside.
This patch adds 'pod' as an argument of WaitForAttach()
and adds changes to drivers who implements WaitForAttach().
Fixes#48953
