Add attribute for all vendor hwservice.

Bug: 159707777
Test: make
Change-Id: Ie3ab6d362b970ae8a9f0a8f1c0109bf03d521ce0
diff --git a/public/attributes b/public/attributes
index 3582a09..45900a9 100644
--- a/public/attributes
+++ b/public/attributes
@@ -204,6 +204,9 @@
 # All core domains (as opposed to vendor/device-specific domains)
 attribute coredomain;
 
+# All vendor hwservice.
+attribute vendor_hwservice_type;
+
 # All socket devices owned by core domain components
 attribute coredomain_socket;
 expandattribute coredomain_socket false;