turned off - accessing userland memory. Now, arch_thread_enter_userspace() does that
job, and as a result, may also fail.
* dump_thread() now directly prints the info of the current thread when used without
argument (rather than iterating the thread list to look for the current thread).
* If arch_thread_init_tls() fails upon thread creation, the function will now return
an error.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@19775 a95241bf-73f2-0310-859d-f6bbb57e9c96