tests: Add some spice gl related virt-xml tests

tests/cli-test-xml/compare/virt-xml-edit-graphics-spice-gl.xml

@@ -0,0 +1,13 @@
+         <device path="/dev/tzz"/>
+       </backend>
+     </tpm>
+-    <graphics type="vnc" port="-1" autoport="yes"/>
++    <graphics type="spice" autoport="no">
++      <gl enable="yes"/>
++    </graphics>
+     <sound model="sb16"/>
+     <sound model="es1370"/>
+     <sound model="ich6"/>
+
+Domain 'test-for-virtxml' defined successfully.
+Changes will take effect after the next domain shutdown.

tests/cli-test-xml/compare/virt-xml-edit-video-virtio.xml

@@ -0,0 +1,13 @@
+     <sound model="es1370"/>
+     <sound model="ich6"/>
+     <video>
+-      <model type="vmvga" vram="16384" heads="1" primary="yes"/>
++      <model type="virtio">
++        <acceleration accel3d="yes"/>
++      </model>
+     </video>
+     <video>
+       <model type="cirrus" vram="16384" heads="3"/>
+
+Domain 'test-for-virtxml' defined successfully.
+Changes will take effect after the next domain shutdown.

tests/clitest.py

@@ -870,6 +870,8 @@ c.add_invalid("--edit --memory 200,clearxml=yes")  # clear isn't wired up for me
 c.add_compare("--edit --disk path=/foo/bar,target=fda,bus=fdc,device=floppy,clearxml=yes", "edit-clear-disk")
 c.add_compare("--edit --cpu host-passthrough,clearxml=yes", "edit-clear-cpu")
 c.add_compare("--edit --clock offset=utc,clearxml=yes", "edit-clear-clock")
+c.add_compare("--edit --video clearxml=yes,model=virtio,accel3d=yes", "edit-video-virtio")
+c.add_compare("--edit --graphics clearxml=yes,type=spice,gl=on,listen=none", "edit-graphics-spice-gl")
 
 c = vixml.add_category("add/rm devices", "test-for-virtxml --print-diff --define", compare_check="1.2.2")  # compare_check=input type=keyboard output
 c.add_valid("--add-device --security model=dac")  # --add-device works for seclabel