Move hidl_test to system (as a VTS test).

Test: hidl_test passes
Test: build with BOARD_VNDK_VERSION=current
Bug: 63704014
Change-Id: Ic5005856a6acc028faf11763ac879509a9a0fb69
diff --git a/test/Android.bp b/test/Android.bp
index 6d294ff..e7209d5 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -8,7 +8,6 @@
 
 cc_test {
     name: "hidl_test_client",
-    vendor: true,
     cflags: hidl_flags,
     srcs: ["hidl_test_client.cpp", "FooCallback.cpp"],
 
@@ -53,7 +52,6 @@
 
 cc_test {
     name: "hidl_test_servers",
-    vendor: true,
     srcs: ["hidl_test_servers.cpp"],
     gtest: false,