numa: forbid '-numa node, mem' for 5.1 and newer machine types

Deprecation period is run out and it's a time to flip the switch
introduced by cd5ff8333a.  Disable legacy option for new machine
types (since 5.1) and amend documentation.

'-numa node,memdev' shall be used instead of disabled option
with new machine types.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200609135635.761587-1-imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/hw/i386/pc_q35.c b/hw/i386/pc_q35.c
index 46cd065..047ea8d 100644
--- a/hw/i386/pc_q35.c
+++ b/hw/i386/pc_q35.c
@@ -369,6 +369,7 @@
 {
     pc_q35_5_1_machine_options(m);
     m->alias = NULL;
+    m->numa_mem_supported = true;
     compat_props_add(m->compat_props, hw_compat_5_0, hw_compat_5_0_len);
     compat_props_add(m->compat_props, pc_compat_5_0, pc_compat_5_0_len);
 }