'defaultStore' can be '' or null, so check for truthyness also, we
want the mapping to be a formField so that the validation triggers
and the restore button gets en/disabled accordingly. We still have to
call 'getValue' manually, because the onGetValues will get it as
string instead of an array
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>