TEST_BPF_MAP -> BPF_MAP_MAKE_VISIBLE_FOR_TESTING

Per request of Lorenzo on:
  https://googleplex-android-review.git.corp.google.com/c/platform/frameworks/libs/net/+/18694820
  https://googleplex-android-review.git.corp.google.com/c/platform/packages/modules/Connectivity/+/18695355

Although he'd suggested 'BPF_MAP_TEST_ONLY',
but I think this is even clearer.

Test: TreeHugger
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I796c939cba8866aca15f3dfff5a27ba986f74df6
diff --git a/netd/BpfHandlerTest.cpp b/netd/BpfHandlerTest.cpp
index d946fea..c0f7e45 100644
--- a/netd/BpfHandlerTest.cpp
+++ b/netd/BpfHandlerTest.cpp
@@ -21,7 +21,7 @@
 
 #include <gtest/gtest.h>
 
-#define TEST_BPF_MAP
+#define BPF_MAP_MAKE_VISIBLE_FOR_TESTING
 #include "BpfHandler.h"
 
 using namespace android::bpf;  // NOLINT(google-build-using-namespace): exempted