Temporarily disable art-tests for userfaultfd GC

Some structural redifinition and jvmti tagging related tests are failing
as of now with userfaultfd GC. These are expected to be fixed once
the userfaultfd GC implementation is finished.

Bug: 242181443
Bug: 243181908
Test: ART_USE_READ_BARRIER=false art/test/testrunner/testrunner.py
--host

Change-Id: If219e7ee0f33a977f6c9d4efcc42a6be86681533
diff --git a/test/knownfailures.json b/test/knownfailures.json
index 0808ee7..9b73518 100644
--- a/test/knownfailures.json
+++ b/test/knownfailures.json
@@ -1333,6 +1333,16 @@
         "description": ["Test containing Checker assertions expecting Baker read barriers."]
     },
     {
+        "tests": ["2009-structural-local-ref",
+                  "2035-structural-native-method",
+	          "2036-structural-subclass-shadow",
+	          "2040-huge-native-alloc",
+	          "905-object-free"],
+        "env_vars": {"ART_USE_READ_BARRIER": "false"},
+        "bug": "b/242181443",
+        "description": ["Tests temporarily disabled for userfaultfd GC. Remove once native GC-root updation is implemented."]
+    },
+    {
         "tests": ["1004-checker-volatile-ref-load"],
         "env_vars": {"ART_READ_BARRIER_TYPE": "TABLELOOKUP"},
         "bug": "b/140507091",