tests: qemuxml2argv: remove some QEMU_CAPS_DEVICE problem cases

When we unconditionally enable QEMU_CAPS_DEVICE, these tests need
some massaging, so do it ahead of time to not mix it in with the
big test refresh.

- minimal-s390 is not a real world working config, so drop it
- disk-usb was testing for an old code path that will be removed.
  instead use it to test lack of USB disk support, and rename it
  to disk-usb-nosupport. Switch xml2xml to use disk-usb-device for
  input.
- cputune-numatune was needlessly using q35, switch it to an older
  machine type

tests/qemuxml2xmloutdata/qemuxml2xmlout-cputune-numatune.xml

@@ -13,7 +13,7 @@
     <memory mode='strict' placement='auto'/>
   </numatune>
   <os>
-    <type arch='x86_64' machine='pc-q35-2.3'>hvm</type>
+    <type arch='x86_64' machine='pc'>hvm</type>
     <boot dev='hd'/>
   </os>
   <clock offset='utc'/>
@@ -22,16 +22,8 @@
   <on_crash>destroy</on_crash>
   <devices>
     <emulator>/usr/bin/qemu-system-x86_64</emulator>
-    <controller type='sata' index='0'>
-      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
-    </controller>
-    <controller type='pci' index='0' model='pcie-root'/>
-    <controller type='pci' index='1' model='dmi-to-pci-bridge'>
-      <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/>
-    </controller>
-    <controller type='pci' index='2' model='pci-bridge'>
-      <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/>
-    </controller>
+    <controller type='usb' index='0'/>
+    <controller type='pci' index='0' model='pci-root'/>
     <input type='mouse' bus='ps2'/>
     <input type='keyboard' bus='ps2'/>
     <memballoon model='none'/>

tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-usb-device.xml

@@ -15,21 +15,19 @@
   <devices>
     <emulator>/usr/bin/qemu</emulator>
     <disk type='block' device='disk'>
-      <driver name='qemu' type='raw'/>
       <source dev='/dev/HostVG/QEMUGuest1'/>
       <target dev='hda' bus='ide'/>
       <address type='drive' controller='0' bus='0' target='0' unit='0'/>
     </disk>
     <disk type='file' device='disk'>
-      <driver name='qemu' type='raw'/>
       <source file='/tmp/usbdisk.img'/>
       <target dev='sda' bus='usb'/>
     </disk>
     <controller type='usb' index='0'/>
-    <controller type='ide' index='0'/>
     <controller type='pci' index='0' model='pci-root'/>
+    <controller type='ide' index='0'/>
     <input type='mouse' bus='ps2'/>
     <input type='keyboard' bus='ps2'/>
-    <memballoon model='none'/>
+    <memballoon model='virtio'/>
   </devices>
 </domain>