AML: Allow Field in ToInteger (rebased)

[rw-vanc]

This PR replaces #209 - it is just a rebase, but I wanted to do it cleanly.

On my HP Laptop, Field is used as argument to ToInteger, even though the spec says it is not an option.

This is the declaration of VDID.

            OperationRegion (RPXX, SystemMemory, GMIO (^_ADR, _ADR), 0x10)

   1737E: 5B 80 52 50 58 58 00 47 4D 49 4F 5E 5F 41 44 52  // [.RPXX.GMIO^_ADR
   1738E: 5F 41 44 52 0A 10                                // _ADR..

            Field (RPXX, AnyAcc, NoLock, Preserve)
            {
                VDID,   32
            }


   17394: 5B 81 0B 52 50 58 58 00 56 44 49 44 20           // [..RPXX.VDID 

Here is where VDID is used in a Switch statement, causing the parser error.

            Method (WIST, 0, Serialized)
            {

   173CD: 14 4A 14 57 49 53 54 08                          // .J.WIST.


   173D5: 08 5F 54 5F 30 00                                // ._T_0.

                If (CondRefOf (VDID))
                {

   173DB: A0 48 13 5B 12 56 44 49 44 00                    // .H.[.VDID.

                    Switch (ToInteger (VDID))
                    {

   173E5: A2 4E 12 01 70 99 56 44 49 44 00 5F 54 5F 30     // .N..p.VDID._T_0

                        Case (0x095A8086)
                        {

   173F4: A0 0D 93 5F 54 5F 30 0C 86 80 5A 09              // ..._T_0...Z.

                            Return (One)
                        }

[rw-vanc]

I closed #209 - please refer to the comments there.

[IsaacWoods]

Apologies for the delay in getting back to you.

I'm still wondering a little if this is just weird AML on their part or if we're missing some kind of implicit field conversion that I haven't come across yet, but since this is needed for parsing real tables I'm happy to merge.

Thanks!