usbd: split bus reset into start/end edge events

A driver that can see reset signalling begin has no way to say so: the only
event carries the negotiated speed, which does not exist until the reset
ends. On ChipIdea that left the stack believing it was still configured for
the whole reset window - 3 ms at minimum, tens of milliseconds in practice -
while the controller had already torn its endpoints down, so a class driver
writing in that window primed a disabled endpoint over a zeroed queue head.

Add DCD_EVENT_BUS_RESET_START for the leading edge and rename the existing
event to DCD_EVENT_BUS_RESET_END, keeping DCD_EVENT_BUS_RESET as an alias.
START is optional and END stays self-sufficient, so every other driver and
the unit tests are untouched.

0 files changed, 0 insertions, 0 deletions