Progress on capabilities

Capabilities will be shared among collection of threads. A pager
will have a right to share its own capabilities with its space,
its thread group and its container.

Currently sharing is possible with only all of the caps. Next,
it will be support for cap splitting, granting, and partial sharing
and granting.

include/l4/generic/container.h

@@ -48,6 +48,7 @@ struct container {
 	struct id_pool *space_id_pool;
 
 	struct mutex_queue_head mutex_queue_head; /* Userspace mutex list */
+	struct cap_list cap_list; /* Capabilities shared by whole container */
 
 	/*
 	 * Capabilities that apply to this container