EDAC/mc_sysfs: Increase legacy channel support to 12

EDAC/mc_sysfs: Increase legacy channel support to 12

Newer AMD systems, such as Genoa, can support up to 12 channels per EDAC
"mc" device. These are detected by the device's EDAC module, and the
current EDAC interface is properly enumerated. However, the legacy EDAC
sysfs interface provides device attributes only for channels 0 to 7.
Therefore, channels 8 to 11 will not be visible in the legacy interface.
This was overlooked in the initial support for AMD Genoa.

Add additional device attributes so that up to 12 channels are visible
in the legacy EDAC sysfs interface.

Fixes: e2be5955a886 ("EDAC/amd64: Add support for AMD Family 19h Models 10h-1Fh and A0h-AFh")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20221018153630.14664-1-yazen.ghannam@amd.com