Add rule for proto file so we can write python to use it.

I wrote another tool filter and augment the proto files, but these proto
files need to have a python library for that tool.

Test: m filter_teams && out/host/linux-x86/bin/filter_teams  --filter_teams

Change-Id: I6b259ddda2b6c09d55a9c6d445b96e5b77741f09
diff --git a/android/team_proto/Android.bp b/android/team_proto/Android.bp
index 061e77e..7e2a4c1 100644
--- a/android/team_proto/Android.bp
+++ b/android/team_proto/Android.bp
@@ -27,3 +27,17 @@
         "team.pb.go",
     ],
 }
+
+python_library_host {
+    name: "teams-proto-py",
+    pkg_path: "teams",
+    srcs: [
+        "team.proto",
+    ],
+    libs: [
+        "libprotobuf-python",
+    ],
+    proto: {
+        canonical_path_from_root: false,
+    },
+}