[unification] Remove reference to ZN config file.

Bug: 52720
Change-Id: I0e11107dd502d51e5744a0dd73fb8809ec46b4d0
diff --git a/BUILD.gn b/BUILD.gn
index 42669dd..891f9b2 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -2,8 +2,6 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("$zx_build/public/gn/config/globals.gni")
-
 declare_args() {
   # Enable debug output in the ACPI library (used by the ACPI bus driver).
   acpica_debug_output = false
@@ -242,7 +240,5 @@
 
   # TODO(41663): UBSan has found an instance of undefined behavior in this target.
   # Disable UBSan for this target temporarily until it is migrated into CI/CQ.
-  if (!is_gcc) {
-    cflags += [ "-fno-sanitize=undefined" ]
-  }
+  cflags += [ "-fno-sanitize=undefined" ]
 }