Revert commit 3714613096b1bb7b7a76e9d360106ea19208f243

>    Change Cache lifecycle to match ring lifecycle.
>    Ensure caches are destroyed when device transitions to D3 to prevent
>    assertion failure in xenbus.
>
>    Signed-off-by: Owen Smith <owen.smith@citrix.com>

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Revert commit 80ace57b353764c9165673e021c2a6cf7616a3bb

>    Use new XENBUS CACHE interface rather than local pool code
>
>    Signed-off-by: Paul Durrant <paul.durrant@citrix.com>

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Re-fix issues uncovered by previous reversions.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Merge pull request #34 from pauldu/ca-140184

[CA-140184]

Revert previous commits that add use of XENBUS's CACHE interface to XENVIF (and then modify cache lifecycle to avoid a crash during hibernation).
The reversions undid a couple of other fixes which are re-applied by the third patch.

Approved-By: Ben.Chalmers@citrix.com