This command was turned into a no-op four years ago in

  commit 0c846544
  Author: Peter Xu <peterx@redhat.com>
  Date:   Fri Dec 29 15:31:04 2017 +0800

    hmp: obsolete "info ioapic"

Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>