Global replace of u_int??_t with C9x standard based uintxx_t
in order to remove some tricky and overlapping portability logic
from acinclude.m4 and leave it in only m4/stdint.m4.
('struct usb_ctrl_setup' -> 'struct usb_in_usb_ctrl_setup')
* Renamed 'struct usb_bulk_setup' to 'struct usb_in_usb_bulk_setup' to show
its internal usage