netd: NetlinkHandler: explicitly ignore "platform" and "backlight" events

The new vsync api uses uevents to notify userspace... 60 events/sec. :(
Don't log unexpected event's subsystem if it is one of the known ones.

Change-Id: Ie900898b326c9451b76ac5f6ba047870fd62093a
diff --git a/NetlinkHandler.cpp b/NetlinkHandler.cpp
index 9a0a844..94e9240 100644
--- a/NetlinkHandler.cpp
+++ b/NetlinkHandler.cpp
@@ -52,8 +52,6 @@
         return;
     }
 
-    ALOGV("subsystem %s", subsys);
-
     if (!strcmp(subsys, "net")) {
         int action = evt->getAction();
         const char *iface = evt->findParam("INTERFACE");
@@ -83,6 +81,11 @@
         if (state)
             notifyInterfaceActivity(iface, !strcmp("active", state));
 
+#if !LOG_NDEBUG
+    } else if (strcmp(subsys, "platform") && strcmp(subsys, "backlight")) {
+        /* It is not a VSYNC or a backlight event */
+        ALOGV("unexpected event from subsystem %s", subsys);
+#endif
     }
 }