Fix building simulators (at least on linux. cygwin and mingw might need more work)

Also bump the plugin api version


git-svn-id: svn://svn.rockbox.org/rockbox/trunk@24110 a1c6a512-1295-4272-9138-f99709370657

apps/plugin.c

@@ -681,7 +681,9 @@ static const struct plugin_api rockbox_api = {
     viewportmanager_theme_enable,
     viewportmanager_theme_undo,
 #endif
+#ifndef SIMULATOR
     &errno
+#endif
 };
 
 int plugin_load(const char* plugin, const void* parameter)

apps/plugin.h

@@ -135,7 +135,7 @@ void* plugin_get_buffer(size_t *buffer_size);
 #define PLUGIN_MAGIC 0x526F634B /* RocK */
 
 /* increase this every time the api struct changes */
-#define PLUGIN_API_VERSION 178
+#define PLUGIN_API_VERSION 179
 
 /* update this to latest version if a change to the api struct breaks
    backwards compatibility (and please take the opportunity to sort in any
@@ -860,7 +860,9 @@ struct plugin_api {
                                          struct viewport *viewport);
     void (*viewportmanager_theme_undo)(enum screen_type screen, bool force_redraw);
 #endif
+#ifndef SIMULATOR
     int* __errno;
+#endif
 };
 
 /* plugin header */