usbip: tools: support SuperSpeedPlus devices

usbip: tools: support SuperSpeedPlus devices

USB devices running at SuperSpeedPlus report "10000" or "20000" in
their sysfs speed attribute. usbip currently maps only "5000" to
USB_SPEED_SUPER, so a SuperSpeedPlus device is imported as
USB_SPEED_UNKNOWN.

The attach request is then rejected by vhci_hcd:

  vhci_hcd: Failed attach request for unsupported USB speed: UNKNOWN

Map the SuperSpeedPlus sysfs speed values to USB_SPEED_SUPER_PLUS, use
the SuperSpeed VHCI hub for SuperSpeedPlus devices, and recognize the
gadget current_speed string used by the kernel.

Fixes: b2316645ca5e ("usb: show speed "10000" in sysfs for USB 3.1 SuperSpeedPlus devices")
Cc: stable <stable@kernel.org>
Signed-off-by: Yichong Chen <chenyichong@uniontech.com>
Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
Link: https://patch.msgid.link/00C828F338E43447+20260617020613.199086-1-chenyichong@uniontech.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>