EDAC, ghes: Add platform check

EDAC, ghes: Add platform check

The ghes_edac driver was introduced in 2013 [1], but it has not been
enabled by any distro yet. This driver obtains error info from firmware
interfaces (APEI), which are not properly implemented on many platforms,
as the driver says on load:

  This EDAC driver relies on BIOS to enumerate memory and get error
  reports. Unfortunately, not all BIOSes reflect the memory layout
  correctly. So, the end result of using this driver varies from vendor
  to vendor. If you find incorrect reports, please contact your hardware
  vendor to correct its BIOS.

To get out from this situation, add a platform check to selectively
enable the driver on platforms that are known to have proper APEI
firmware implementation.

"ghes_edac.force_load=1" skips this platform check.

[1]: https://lkml.kernel.org/r/cover.1360931635.git.mchehab@redhat.com

Signed-off-by: Toshi Kani <toshi.kani@hpe.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-acpi@vger.kernel.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170823225447.15608-4-toshi.kani@hpe.com
Signed-off-by: Borislav Petkov <bp@suse.de>