EDAC/mc: Remove per layer counters

Looking at how mci->{ue,ce}_per_layer[EDAC_MAX_LAYERS] is used, it
turns out that only the leaves in the memory hierarchy are consumed
(in sysfs), but not the intermediate layers, e.g.:

  count = dimm->mci->ce_per_layer[dimm->mci->n_layers-1][dimm->idx];

These unused counters only add complexity, remove them. The error
counter values are directly stored in struct dimm_info now.

Signed-off-by: Robert Richter <rrichter@marvell.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Aristeu Rozanski <aris@redhat.com>
Link: https://lkml.kernel.org/r/20200123090210.26933-11-rrichter@marvell.com