Add missing delete routine to SyncThread

BlockedWaitNoTimeline is still used as async fence callback isn't 100%
rolled out yet. However, it's missing a call to sweep old FenceSync's
away. This can help with leaked sync objects.

Change-Id: I9a136e745682e6ac42cfce7814924146c1dd01f4
diff --git a/stream-servers/SyncThread.cpp b/stream-servers/SyncThread.cpp
index acc672c..0ce5a0e 100644
--- a/stream-servers/SyncThread.cpp
+++ b/stream-servers/SyncThread.cpp
@@ -470,6 +470,8 @@
         fprintf(stderr, "error: eglClientWaitSync abnormal exit 0x%x %p %#x\n",
                 wait_result, cmd->fenceSync, error);
     }
+
+    FenceSync::incrementTimelineAndDeleteOldFences();
 }
 
 void SyncThread::doExit(SyncThreadCmd* cmd) {