EDAC/amd64: Split setup_mci_misc_attrs() into dct/umc functions

The init_one_instance() path is shared between legacy and modern
systems. So add the new functions to a function pointer in pvt->ops.

No functional change is intended.

  [ Yazen: Rebased/reworked patch and reworded commit message. ]

Signed-off-by: Muralidhara M K <muralidhara.mk@amd.com>
Co-developed-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Signed-off-by: Naveen Krishna Chatradhi <naveenkrishna.chatradhi@amd.com>
Co-developed-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230127170419.1824692-18-yazen.ghannam@amd.com