docs/qdev-device-use.txt: Update section "Default Devices"

Resynchronize the table of default device suppressions with vl.c's
default_list[].
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20200622094227.1271650-8-armbru@redhat.com>

docs/qdev-device-use.txt

@@ -384,8 +384,8 @@ some DEVNAMEs:
     parallel            isa-parallel
     serial              isa-serial
     VGA                 VGA, cirrus-vga, isa-vga, isa-cirrus-vga,
-                        vmware-svga, qxl-vga, virtio-vga
-    virtioconsole       virtio-serial-pci, virtio-serial
+                        vmware-svga, qxl-vga, virtio-vga, ati-vga,
+                        vhost-user-vga
 
 The default NIC is connected to a default part created along with it.
 It is *not* suppressed by configuring a NIC with -device (you may call