Add support for NCT6683D series

[chencaidy]

Add support for Nuvoton NCT6683D/NCT6686D/NCT6687D,
it tested on ThinkCentre M920x with NCT6686D EC, use Macmini8,1 SMBIOS

I tested unplug the fan connector, F0Ac return zero soon.
smcread logs:
[F0Ac] type [fpe2] 66706532 len [ 2] attr [80] -> 193C
[F1Ac] type [fpe2] 66706532 len [ 2] attr [80] -> 0000
[F2Ac] type [fpe2] 66706532 len [ 2] attr [80] -> 0000
[F3Ac] type [fpe2] 66706532 len [ 2] attr [80] -> 0000
[F4Ac] type [fpe2] 66706532 len [ 2] attr [80] -> 0000

But voltage function seems are programable regs and programed by OEM,
so it marked with todo.

[chencaidy]

Hi @vit9696,

Voltage read seems working on NCT6683,

It reported VIN0, VIN1 and VIN3 from ThineCentre M920x.

    | |   | +-o SMCSuperIO  <class SMCSuperIO, id 0x1000002c9, !registered, !matched, active, busy 0, retain 6>
    | |   | |   {
    | |   | |     "IOClass" = "SMCSuperIO"
    | |   | |     "CFBundleIdentifier" = "ru.joedm.SMCSuperIO"
    | |   | |     "IOProviderClass" = "IOPCIDevice"
    | |   | |     "VersionInfo" = "REL-123-2021-05-07"
    | |   | |     "IOPCIClassMatch" = "0x06010000&0xffff0000"
    | |   | |     "IOPowerManagement" = {"CapabilityFlags"=32770,"MaxPowerState"=1,"CurrentPowerState"=1}
    | |   | |     "ChipName" = "Nuvoton NCT6686D"
    | |   | |     "IOResourceMatch" = "ACPI"
    | |   | |     "IOProbeScore" = 0
    | |   | |     "Sensors" = {"VIN12"=<00000000>,"VTT"=<00000000>,"3VCC"=<00000000>,"VIN11"=<00000000>,"VIN3"=<1b2fdd3e>,"VIN16"=<00000000>,"VIN8"=<00000000>,"VIN10"=<00000000>,"SYSFAN"=0,"VBAT"=<00000000>,"VIN1"=<b91e853f>,"CPUFAN"=1602,"VIN6"=<00000000>,"VIN15"=<00000000>,"VREF"=<00000000>,"VIN14"=<00000000>,"VIN4"=<00000000>,"AUXFAN0"=0,"3VSB"=<00000000>,"VIN9"=<00000000>,"VIN13"=<00000000>,"VIN2"=<00000000>,"AUXFAN1"=0,"VIN7"=<00000000>,"VIN0"=<f0a7c63f>,"AUXFAN2"=0,"AVSB"=<00000000>,"VIN5"=<00000000>}
    | |   | |     "IOMatchCategory" = "SMCSuperIO"
    | |   | |     "CFBundleIdentifierKernel" = "ru.joedm.SMCSuperIO"
    | |   | |   }

[vit9696]

Looks nice, approved the CI and left a comment on the code. Thx!