silence warning

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@10210 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/endpoints/mod_portaudio/mod_portaudio.c

@@ -1172,6 +1172,8 @@ static switch_status_t engage_device(int sample_rate, int codec_ms)
 			}
 		}
 
+		switch_assert(globals.read_codec.implementation);
+
 		if (!globals.write_codec.implementation) {
 			if (switch_core_codec_init(&globals.write_codec,
 									   "L16",