lptools: add to build

Use TW_EXCLUDE_LPTOOLS to exclude from build

Will only be included on devices with dynamic partitions

Change-Id: I77092344a1e31e749161cb31e6e020f6e9fc3800
diff --git a/prebuilt/Android.bp b/prebuilt/Android.bp
new file mode 100644
index 0000000..fdbb3d2
--- /dev/null
+++ b/prebuilt/Android.bp
@@ -0,0 +1,5 @@
+soong_namespace {
+    imports: [
+		"external/lptools",
+	],
+}