xen/sched: carve out memory allocation and freeing from schedule_cpu_rm()

xen/sched: carve out memory allocation and freeing from schedule_cpu_rm()

In order to prepare not allocating or freeing memory from
schedule_cpu_rm(), move this functionality to dedicated functions.

For now call those functions from schedule_cpu_rm().

No change of behavior expected.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: d42be6f83480b3ada286dc18444331a816be88a3
master date: 2022-09-05 11:42:30 +0100