usb: Kill left-over cdefs.h includes
These includes were for __FBSD_RCSID() macro. They weren't formatted
like the rest of the tree so weren't trimmed automatically when that
script was run. Trim them now.
MFC After: 1 week
Sponsored by: Netflix
(cherry picked from commit ca48e43ba9ee73a07cdbad8365117793b01273bb)