x86, MCE, AMD: Give proper names to the thresholding banks

Having the banks numbered is ok but having real names which mean
something to the user makes a lot more sense:

 /sys/devices/system/machinecheck/machinecheck0/
 |-- bank0
 |-- bank1
 |-- bank2
 |-- bank3
 |-- bank4
 |-- bank5
 |-- bank6
 |-- check_interval
 |-- cmci_disabled
 |-- combined_unit
 |   |-- combined_unit
 |       |-- error_count
 |       |-- threshold_limit
 |-- dont_log_ce
 |-- execution_unit
 |   |-- execution_unit
 |       |-- error_count
 |       |-- threshold_limit
 |-- ignore_ce
 |-- insn_fetch
 |   |-- insn_fetch
 |       |-- error_count
 |       |-- threshold_limit
 |-- load_store
 |   |-- load_store
 |       |-- error_count
 |       |-- threshold_limit
 |-- monarch_timeout
 |-- northbridge
 |   |-- dram
 |   |   |-- error_count
 |   |   |-- interrupt_enable
 |   |   |-- threshold_limit
 |   |-- ht_links
 |   |   |-- error_count
 |   |   |-- interrupt_enable
 |   |   |-- threshold_limit
 |   |-- l3_cache
 |       |-- error_count
 |       |-- interrupt_enable
 |       |-- threshold_limit
...

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>