Changeset 56d34e6 in rtems for c/src/exec/sapi

Removed the internal thread objects and dispersed its contents to
the thread handler (IDLE), MPCI object (SYSI now MP Receive)
and initialize_executive_early (IO initialization). The SYSI task
no longer exists in a single processor configuration. This reduces
single processor Workspace requirements by a TCB and a stack which
is often larger than the minimum stack size. Moving the IO initialization
plus accompanying BSP hooks eliminated an initialization ordering problem
in which a global task could be created before the MPCI was initialized.