Trailing whitespace.
Remove dwc2_{alloc,free}m function declarations as these don't exist
anymore.
The grand renaming of structure members.

No functional change.
Use designated initialisers for usb_device_descriptor_t structs.
Use designated initializers for more descriptors.
G/C M_USBHC
Replace malloc(9) with kmem(9)
Rearrange the usbd_bus struct member to match the comments about who
fills them.
Remove #include <sys/malloc.h> where it's not (no longer) needed
Provide a USETWD macro for use with USB words designated
initialisers.
Use designated initialisers.  No functional change.
Rename usbroothub_subr.[ch] to usbroothub.[ch]