userspace: add thread-level permission tracking

Now creating a thread will assign it a unique, monotonically increasing
id which is used to reference the permission bitfield in the kernel
object metadata.

Stub functions in userspace.c now implemented.

_new_thread is now wrapped in a common function with pre- and post-
architecture thread initialization tasks.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
5 files changed