WIP: xpadneo, device: Fix up NUL byte before final End Collection

[kakra]

Some firmwares write 0x00 where a second End Collection (0xC0) was needed to close a nested collection, followed by a correct final 0xC0. The HID parser then sees an unknown Main item instead of the closing End Collection, breaking descriptor parsing for the affected report.

Replace the stray 0x00 with 0xC0 so the descriptor ends with two valid End Collections. Do not shrink the descriptor: both bytes are required to close the two open collections.

TODO:

• Needs descriptor dump to find and validate both opening offsets

Link: #603

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@GloriousEggroll Are you able to provide the missing broken descriptor so we can implement this evidence-based?

[GloriousEggroll]

sorry ive been away from this for a little while with other projects taking priority, which device(s) did you need descriptor dumps from?

[kakra]

I have two queued commits which miss descriptors as evidence for the checksums and fixups:

New known checksums:

- Xbox One Elite Series 2 legacy firmware
- Xbox One S 1708 (fw 0x0903 with truncated rumble descriptor)

From the C code:

{ .crc16 = 0x28FA, .name = "Xbox One Elite Series 2 (legacy)" },
{ .crc16 = 0x6BA1, .name = "Xbox One S 1708 (fw 0x0903, truncated rumble descriptor)" },