afdo_metadata: Remove the entry for 3.14

Since we do not update AFDO profiels for kernel 3.14 anymore,
there is no need to keep the entry.

BUG=None
TEST=None

Change-Id: If39a5beabd246a703c3aeb458a27ec450a88dffe
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/2236653
Reviewed-by: Tiancong Wang <tcwang@google.com>
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Commit-Queue: Tiancong Wang <tcwang@google.com>
Tested-by: Tiancong Wang <tcwang@google.com>
diff --git a/afdo_metadata/kernel_afdo.json b/afdo_metadata/kernel_afdo.json
index 5c738b3..f66f7e7 100644
--- a/afdo_metadata/kernel_afdo.json
+++ b/afdo_metadata/kernel_afdo.json
@@ -1,7 +1,4 @@
 {
-    "chromeos-kernel-3_14": {
-        "name": "R81-12607.58-1578524353"
-    },
     "chromeos-kernel-4_4": {
         "name": "R85-13261.0-1591609702"
     },