fix small leak in wait_for_silence

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@9452 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/switch_ivr_play_say.c

@@ -1354,6 +1354,7 @@ SWITCH_DECLARE(switch_status_t) switch_ivr_wait_for_silence(switch_core_session_
 
 	if (abuf) {
 		switch_core_file_close(&fh);
+		free(abuf);
 	}
 
 	return status;