Remove broken getvolumename and pass PV or volume name to attach call

[chakri-nelluri]

What this PR does / why we need it:
Flex getvolumename is broken in 1.6. It needs to be fixed comprehensively in 1.7 release. Removing the api in 1.6. Also pass PV or volume name to the driver during attach call. Detach uses PV or volume name, so plugin can use that information to map to PV.
Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #
Fixes - #44737

[k8s-ci-robot]

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[k8s-github-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: chakri-nelluri
We suggest the following additional approver: brendandburns

Assign the PR to them by writing /assign @brendandburns in a comment when ready.

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[k8s-github-robot]

This PR is not for the master branch but does not have the cherrypick-approved label. Adding the do-not-merge label.

[saad-ali]

Will we want it in the API once the "mount metadata file" fix is in? If so, instead of taking it out and adding it back in maybe leave it in with a warning?

[chakri-nelluri]

Thanks @saad-ali. Kept the API call. Added warning and defaulted to spec Name.

[enisoc]

Please rebase this PR on the release-1.6 branch. The release-1.6.3 branch was for a special one-off fix and will not be used for any further development.

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[chakri-nelluri]

Thanks @enisoc. Create new PR #46249 & pointed to release-1.6