tests: really fix QEMU XML-2-ARGV graphics-spice-timeout test

Alas, /usr/bin/kvm is also not directly supported by testutilsqemu.c.

In fact, _any_ test that uses <cpu match=...> has to use our faked
qemu.sh in order to properly answer the 'qemu -cpu ?' probe done
during qemu command line building.

* tests/qemuxml2argvdata/*graphics-spice-timeout*: Switch emulator, again.

tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-timeout.args

 LC_ALL=C PATH=/bin HOME=/home/test USER=test LOGNAME=test QEMU_AUDIO_DRV=spice \
-/usr/bin/kvm -S -M pc-0.13 -cpu core2duo,+lahf_lm,+xtpr,+cx16,+tm2,\
+./qemu.sh -S -M pc -cpu core2duo,+lahf_lm,+xtpr,+cx16,+tm2,\
 +est,+vmx,+ds_cpl,+pbe,+tm,+ht,+ss,+acpi,+ds \
 -m 1024 -smp 2 -nodefaults -monitor unix:/tmp/test-monitor,server,nowait \
 -boot dc -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6 \

tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-timeout.xml

@@ -5,7 +5,7 @@
   <currentMemory>1048576</currentMemory>
   <vcpu>2</vcpu>
   <os>
-    <type arch='x86_64' machine='pc-0.13'>hvm</type>
+    <type arch='i686' machine='pc'>hvm</type>
     <boot dev='cdrom'/>
     <boot dev='hd'/>
     <bootmenu enable='yes'/>
@@ -38,7 +38,7 @@
   <on_reboot>restart</on_reboot>
   <on_crash>restart</on_crash>
   <devices>
-    <emulator>/usr/bin/kvm</emulator>
+    <emulator>/./qemu.sh</emulator>
     <disk type='file' device='disk'>
       <driver name='qemu' type='qcow2'/>
       <source file='/var/lib/libvirt/images/f14.img'/>