eco32: implement init_new_context in mmu_context.h

+ minor style fix

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

All IO devices are in the direct mapped range,
so there are nothing to be done for any other addresses.
Possible future improvement, disallow accesses into RAM,
but that would require knowledge how the RAM is
mapped into the direct mapped area.

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