Revert "microkernel: Add support for *_sleep() during initialization"

This reverts commit 0d50329105b74b361d04237d44823bf55b0dc9b3.

This breaks sanitychecks in CI. The early_sleep kernel test case is failing
randomly.

Change-Id: I015f20699c052b4089076699fc0180945c4d3d16
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
5 files changed