init: Add init system calls to micro and nano kernel init

Add the call sites for the various init levels defined by the init
system.

These call sites are noops if there is no init proceedure registered
at a given init level.

pre_app_init has been renamed to app_early_init and late_initconfig to
app_late_init to better reflect the ordering and intended use of these
init levels

Change-Id: I71e38d936a97da8fe163f4b7cf0ce6725f1c903e
Signed-off-by: Dirk Brandewie <dirk.j.brandewie@intel.com>