schemas: Allow additional qemu cmd line arguments/env variables and qemuCaps to be interleaved

While command line arguments are sort of positional (because you
have to have two entries, one for "-arg" the other for "value"),
it doesn't really matter whether env variables come before or
after command line arguments.

And it matters even less when playing with qemu capabilities.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Reviewed-by: NFabiano Fidêncio <fidencio@redhat.com>
Reviewed-by: NCole Robinson <crobinso@redhat.com>

docs/schemas/domaincommon.rng

@@ -6295,37 +6295,41 @@
     -->
   <define name="qemucmdline">
     <element name="commandline" ns="http://libvirt.org/schemas/domain/qemu/1.0">
-      <zeroOrMore>
-        <element name="arg">
-          <attribute name='value'/>
-        </element>
-      </zeroOrMore>
-      <zeroOrMore>
-        <element name="env">
-          <attribute name='name'>
-            <ref name="filter-param-name"/>
-          </attribute>
-          <optional>
+      <interleave>
+        <zeroOrMore>
+          <element name="arg">
             <attribute name='value'/>
-          </optional>
-          <empty/>
-        </element>
-      </zeroOrMore>
+          </element>
+        </zeroOrMore>
+        <zeroOrMore>
+          <element name="env">
+            <attribute name='name'>
+              <ref name="filter-param-name"/>
+            </attribute>
+            <optional>
+              <attribute name='value'/>
+            </optional>
+            <empty/>
+          </element>
+        </zeroOrMore>
+      </interleave>
     </element>
   </define>
 
   <define name="qemucapabilities">
     <element name="capabilities" ns="http://libvirt.org/schemas/domain/qemu/1.0">
-      <zeroOrMore>
-        <element name="add">
-          <attribute name="capability"/>
-        </element>
-      </zeroOrMore>
-      <zeroOrMore>
-        <element name="del">
-          <attribute name="capability"/>
-        </element>
-      </zeroOrMore>
+      <interleave>
+        <zeroOrMore>
+          <element name="add">
+            <attribute name="capability"/>
+          </element>
+        </zeroOrMore>
+        <zeroOrMore>
+          <element name="del">
+            <attribute name="capability"/>
+          </element>
+        </zeroOrMore>
+      </interleave>
     </element>
   </define>