Changed aos_sync to absl::call_once()

Change-Id: Ib1a87946c0d0dbba681190a175964f99b1c82f07
diff --git a/aos/ipc_lib/BUILD b/aos/ipc_lib/BUILD
index 1e8b118..684620a 100644
--- a/aos/ipc_lib/BUILD
+++ b/aos/ipc_lib/BUILD
@@ -13,7 +13,7 @@
     ],
     deps = [
         "//aos:macros",
-        "//aos:once",
+        "@com_google_absl//absl/base",
         "//aos/logging",
         "//aos/util:compiler_memory_barrier",
     ],