Separate AVFHostTestCases from avf-postsubmit

AVFHostTestCases wouldn't run on user build,
so separate it to differentiate postsubmits per build type.

Bug: 267972709
Test: N/A
Change-Id: Iebc9f23cf7f4091852da16ab7789db88109cef6c
diff --git a/TEST_MAPPING b/TEST_MAPPING
index 14452a3..ea3ab74 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -34,7 +34,9 @@
     },
     {
       "name": "ComposBenchmarkApp"
-    },
+    }
+  ],
+  "avf-postsubmit-userdebug": [
     {
       "name": "AVFHostTestCases"
     }