XHCI: Provide USB 3.2 support

[cocobean]

The USB 3.2 standard is backward compatible with USB 3.1/3.0 and USB 2.0. It defines the following transfer modes:

    USB 3.2 Gen 1×1 – SuperSpeed, 5 Gbit/s (0.500 GB/s) data signaling rate over 1 lane using 8b/10b encoding, the same as USB 3.1 Gen 1 and USB 3.0.
    USB 3.2 Gen 1×2 – SuperSpeed+, new 10 Gbit/s (1.00 GB/s) data rate over 2 lanes using 8b/10b encoding.
    USB 3.2 Gen 2×1 – SuperSpeed+, 10 Gbit/s (~1.2 GB/s) data rate over 1 lane using 128b/132b encoding, the same as USB 3.1 Gen 2.
    USB 3.2 Gen 2×2 – SuperSpeed+, new 20 Gbit/s (~2.4 GB/s) data rate over 2 lanes using 128b/132b encoding

NOTE: USB 3.2 is supported in Windows 10 and Linux 4.18 USB 3.x drivers

SPEC: ​https://usb.org/usb-32 (USB 3.2, Date: V1.0, Sept 22, 2017)

[waddlesplash]

The entire point of XHCI was to abstract away future changes to the USB specification inside the controller, rather than inside the drivers. So, unless you have a USB 3.2 device that you can show works in "USB 3.2 mode" under Linux but not under Haiku, there is nothing to do here.

[cocobean]

Ok. My Lexar 128 USB 3.1 drive works in USB 2.0 mode with hrev53636. Will test "USB 3.2 mode" controller and drive issues in future releases.

[waddlesplash]

If it is running in USB 2.0 mode, this must mean it is on a USB 2 port or hub. All USB 3+ devices should operate in USB 3.0 mode at the very least, if plugged in to the appropriate port.