move bpf test map into a separate file

This allows for better separation of test vs production code:
we will add more test maps and programs here later.

Test: builds
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I7b22e3e148ebf43fdf43dc68d0dea354f7627688
diff --git a/Tethering/bpf_progs/Android.bp b/Tethering/bpf_progs/Android.bp
index d54f861..d62e9a1 100644
--- a/Tethering/bpf_progs/Android.bp
+++ b/Tethering/bpf_progs/Android.bp
@@ -31,3 +31,18 @@
         "system/netd/libnetdutils/include",  // for UidConstants.h
     ],
 }
+
+bpf {
+    name: "test.o",
+    srcs: ["test.c"],
+    cflags: [
+        "-Wall",
+        "-Werror",
+    ],
+    include_dirs: [
+        // TODO: get rid of system/netd.
+        "system/netd/bpf_progs",             // for bpf_net_helpers.h
+        "system/netd/libnetdbpf/include",    // for bpf_shared.h
+        "system/netd/libnetdutils/include",  // for UidConstants.h
+    ],
+}