More type fixes

Param ids and IO ids are now simple enums.
Move some type info in one place, delete some type-info files
Fix type debug
Make audio layout an enum
Mark more enums as enums in types so they show us with their names in
the debug.

spa/include/spa/node/io.h

@@ -25,6 +25,7 @@ extern "C" {
 #endif
 
 #include <spa/utils/defs.h>
+#include <spa/pod/pod.h>
 
 /** Buffers IO area
  *
@@ -32,6 +33,17 @@ extern "C" {
  * by the host and configured on all ports for which IO is requested.
  */
 
+/** Different IO area types */
+enum spa_io_type {
+	SPA_IO_BASE,
+
+	SPA_IO_Buffers,
+	SPA_IO_ControlRange,
+	SPA_IO_Clock,
+	SPA_IO_Latency,
+	SPA_IO_Events,
+};
+
 struct spa_io_buffers {
 #define SPA_STATUS_OK			0
 #define SPA_STATUS_NEED_BUFFER		(1<<0)
@@ -69,6 +81,11 @@ struct spa_io_latency {
 	uint64_t max;			/**< max latency */
 };
 
+/** event stream */
+struct spa_io_events {
+	struct spa_pod_sequence sequence;	/**< sequence of timed events */
+};
+
 #ifdef __cplusplus
 }  /* extern "C" */
 #endif