Update gstreamer x264enc parameters (#912)

Author: qwu16

source/agent/plugins/samples/cpu_pipeline/mypipeline.cc

@@ -127,13 +127,12 @@ rvaStatus MyPipeline::LinkElements() {
 
     g_object_set(G_OBJECT(source),"is-live", true, NULL);
 
-    g_object_set(G_OBJECT(encoder),"pass", 5,
-		    "quantizer", 25,
+    g_object_set(G_OBJECT(encoder),
 		    "speed-preset", 6,
 		    "bitrate", 812,
 		    "aud", false,
 		    "tune", 0x00000004,
-		    "key-int-max", 30, NULL);
+		    "key-int-max", 100, NULL);
 
     g_object_set(G_OBJECT(outsink), "max-buffers", 1,
 		    "sync", false,