tests: Fix breakage with libvirt.git

https://ci.centos.org/job/virt-manager-master-check/systems=libvirt-fedora-rawhide/409/

Added validation to hugepages nodeset. Just drop the test case, we
test it elsewhere too

tests/xmlparse-xml/change-guest-out.xml

@@ -100,7 +100,7 @@
   </memtune>
   <memoryBacking>
     <hugepages>
-      <page size="1" unit="G" nodeset="1,5-8"/>
+      <page size="1" unit="G"/>
     </hugepages>
     <nosharepages/>
     <locked/>

tests/xmlparse.py

@@ -216,7 +216,6 @@ class XMLParseTest(unittest.TestCase):
         check("hugepages", False, True)
         check("page_size", None, 1)
         check("page_unit", None, "G")
-        check("page_nodeset", None, "1,5-8")
         check("nosharepages", False, True)
         check("locked", False, True)