exclude CRYPTO_zalloc from lsan checks

Summary:
https://www.internalfb.com/intern/everpaste/?color=1&handle=GN5JpwdQGnzdG_YHAI7oHZnLbA9Obr0LAAAz

Above run and most other agent hw test runs see the lsan leaks with this symbol. Excluding it from lsan checks.

Reason for the leak is unknown but this change will atleast keep the on-diffs from getting disabled due to bad signal.

Reviewed By: zechengh09

Differential Revision: D63340317

fbshipit-source-id: 999ec66edbd2e036960fdd44b4c2d168fb54af83

fboss/BUILD_MODE.bzl

@@ -49,6 +49,7 @@ _lsan_suppressions = [
     # TODO  Remove the below as part of T143911621
     # Disable asan warning till DLB warmboot support implemented
     "bcm_th2_l3_egress_dlb_attr_set",
+    "CRYPTO_zalloc",
 ]
 
 _tsan_suppressions = [