xhci(4): Ensure the so-called data toggle gets properly reset.
Use the drop and enable endpoint context commands to force a reset of
the data toggle for USB 2.0 and USB 3.0 after:
- clear endpoint halt command (when the driver wishes).
- set config command (when the kernel or user-space wants).
- set alternate setting command (only affected endpoints).
Some XHCI HW implementations may not allow the endpoint reset command when
the endpoint context is not in the halted state.
Reported by: Juniper and Gary Jennejohn
MFC after: 1 week
Sponsored by: NVIDIA Networking