Handle task spawn attributes as task spawn file actions are handled.
Why? This removes the need for sched_lock() when the task is being
spawned. When loading the new task from a file the scheduler can be
locked for a VERY LONG time, in the order of hundreds of milliseconds!
This is unacceptable for real time operation.
Also fixes a latent bug in exec_module, spawn_file_actions is executed
at a bad location; when CONFIG_ARCH_ADDRENV=y actions will point to the
new process's address environment (as it is temporarily instantiated at
that point). Fix this by moving it to after addrenv_restore.
ab78e3817a