EDAC, skx_common: Separate common code out from skx_edac

EDAC, skx_common: Separate common code out from skx_edac

Parts of skx_edac can be shared with the Intel 10nm server EDAC driver.

Carve out the common parts from skx_edac in preparation to support both
skx_edac driver and i10nm_edac drivers.

Co-developed-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: James Morse <james.morse@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: https://lkml.kernel.org/r/20190130191519.15393-3-tony.luck@intel.com