eco32: fail in do_work_pending with a more descriptive message

do_work_pending should only be called with
_TIF_NOTIFY_RESUME, _TIF_SIGPENDING or _TIF_NEED_RESCHED set,
everything else is an error.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
eco32: remove early_init_dt_setup_initrd_arch

This is not needed for archs to perform anymore.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
eco32: clean-up process.c

Remove excessive includes and "SJK TODOs"
eco32: fix delay implementation

This implements __delay as a (tight) loop.
This means that we will need to rely on the "heavy-weight"
calibration to obtain loops_per_jiffy.

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
eco322: use generic delay calibration

Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>