UBUNTU: [Config] Change Config Option CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE for s390x...

UBUNTU: [Config] Change Config Option CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE for s390x from yes to no

BugLink: https://bugs.launchpad.net/bugs/1848492
Having CONFIG_MEMORY_HOTPLUG_DEFAULT_ONLINE disabled makes sure that
memory that is configured as 'Reserved' to an s390x LPAR (on top of memory
that is configured as 'Initial') is no longer automatically consumed (means
set online) at boot time and can now be dynamically added later on demand.

Signed-off-by: Frank Heimes <frank.heimes@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Souza <kleber.souza@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>