i3200_edac: convert driver to use the new edac ABI

The legacy edac ABI is going to be removed. Port the driver to use
and benefit from the new API functionality.

Cc: Hitoshi Mitake <h.mitake@gmail.com>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>