EDAC/skx_common: Enable EDAC support for the "near" memory

The current {skx,i10nm}_edac miss the EDAC support to decode errors from
the 1st level memory (the fast "near" memory as cache) of the 2-level
memory system. Introduce a helper function skx_error_in_mem() to check
whether errors are from memory at the beginning of skx_mce_check_error().

As long as the errors are from memory (either the 1-level memory system
or the 2-level memory system), decode the errors.

Reported-and-tested-by: Youquan Song <youquan.song@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: https://lore.kernel.org/all/20230113032802.41752-1-qiuxu.zhuo@intel.com