Remove TEST_MAPPING, failing rust tests

* rvc-dev has out-of-date .bp and TEST_MAPPING files,
  whose failing tests were ignored but now detected by
  newer tradefed test runners.
* Remove/ignore these tests for rvc-dev and down-stream branches.

Bug: b/162561729
Test: make and atest
Merged-In: I684f2dd5e1ff4de630b031c9e135990ed63e04a1
Change-Id: Ifd08d28de7349755edf7130234510ca333b1fdaa
diff --git a/TEST_MAPPING b/TEST_MAPPING
deleted file mode 100644
index acd1a0c..0000000
--- a/TEST_MAPPING
+++ /dev/null
@@ -1,24 +0,0 @@
-{
-  "presubmit": [
-    {
-      "name": "proc-macro2_tests_proc_macro2",
-      "host": true
-    },
-    {
-      "name": "proc-macro2_tests_features",
-      "host": true
-    },
-    {
-      "name": "proc-macro2_tests_marker",
-      "host": true
-    },
-    {
-      "name": "proc-macro2_tests_test",
-      "host": true
-    },
-    {
-      "name": "proc-macro2_tests_marker",
-      "host": true
-    }
-  ]
-}