The edac driver for Sandy Bridge was found to be reporting "FPM"
for edac_mode, which clearly doesn't make sense. It was found that
sb_edac.c:get_dimm_config was reusing a variable for both mem_type
and edac_type, and thus was overwriting the value after setting
it correctly. This patch fixes that issue.

Before the patch:
/sys/devices/system/edac/mc/mc0/csrow0/edac_mode:FPM
/sys/devices/system/edac/mc/mc0/csrow1/edac_mode:FPM
/sys/devices/system/edac/mc/mc0/csrow2/edac_mode:FPM
/sys/devices/system/edac/mc/mc0/csrow3/edac_mode:FPM

After:
/sys/devices/system/edac/mc/mc0/csrow0/edac_mode:S4ECD4ED
/sys/devices/system/edac/mc/mc0/csrow1/edac_mode:S4ECD4ED
/sys/devices/system/edac/mc/mc0/csrow2/edac_mode:S4ECD4ED
/sys/devices/system/edac/mc/mc0/csrow3/edac_mode:S4ECD4ED
Signed-off-by: NMark A. Grondona <mgrondona@llnl.gov>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

Some changes on it were required due to changeset cd90cc84c6bf0, that
changed the glue with the MCE logic.
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

This driver is known to work on mine and Tony's test environments,
using software error injection, and a partial hardware/software
error injection tool.

There's no broader range test yet to double check if the error decoding
logic will actually point to the right DIMM, so use it with care.
More tests are required to be sure that the driver will work on all
different types of memory configurations.

If you're willing to risk using it, I suggest you to enable EDAC debugs
for your test machines, as the debug logs helps to track what's going
inside the driver.

Please feed me with bug reports, if you notice that the driver
is miss-behaving.
Tested-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>