Remove dynamic types

Do not use dynamic types anymore. The reason is that it's difficult:

- to maintain a shared type database over a network.
- the extra overhead when translating between processes and for
  maintaining the translation tables.
- race conditions in translating in RT-threads, this is a problem
  because we want to make event streams.

We now have simple enums with types and extension points for all
types. This is also nicer to use in general.
We don't need the mapper anymore or pass strings around as types.
There is a parallel type info system to get more info about ids and
enums and their hierarchy. It can also be used for debugging.

spa/include/spa/support/loop.h

@@ -25,16 +25,9 @@ extern "C" {
 #endif
 
 struct spa_loop;
-#define SPA_TYPE__Loop		SPA_TYPE_INTERFACE_BASE "Loop"
-#define SPA_TYPE_LOOP_BASE	SPA_TYPE__Loop ":"
-
 struct spa_loop_control;
-#define SPA_TYPE__LoopControl	SPA_TYPE_INTERFACE_BASE "LoopControl"
 struct spa_loop_utils;
-#define SPA_TYPE__LoopUtils	SPA_TYPE_INTERFACE_BASE "LoopUtils"
-
-#define SPA_TYPE_LOOP__MainLoop		SPA_TYPE_LOOP_BASE "MainLoop"
-#define SPA_TYPE_LOOP__DataLoop		SPA_TYPE_LOOP_BASE "DataLoop"
+struct spa_source;
 
 #include <spa/utils/defs.h>
 #include <spa/utils/hook.h>
@@ -46,8 +39,6 @@ enum spa_io {
 	SPA_IO_ERR = (1 << 3),
 };
 
-struct spa_source;
-
 typedef void (*spa_source_func_t) (struct spa_source *source);
 
 struct spa_source {