ARINC653: fix sched_priv corruption in alloc_vdata

ARINC653: fix sched_priv corruption in alloc_vdata

The ARINC653 scheduler was directly assigning and manipulating
the sched_priv field of a vcpu in its alloc_vdata function.

When creating a cpu pool, this resulted in the corruption
of the sched_priv field of the vcpu, which was then passed
to the initial scheduler's free_vdata function with
disastrous results.

Signed-off-by: Nathan Studer <nate.studer@dornerworks.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>