EDAC: Fix the leak of mci->bus->name when bus_register fails

Also use goto labels for all failure paths in
edac_create_sysfs_mci_device and update meaningless labels.

Signed-off-by: Junjie Mao <junjie.mao@hotmail.com>
Link: http://lkml.kernel.org/r/BLU436-SMTP25291B6B612942A212AEBFE95300@phx.gbl


[ Boris: Use ! for 0 checks and add newlines for less crammed code. ]
Signed-off-by: Borislav Petkov <bp@suse.de>