Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Use DEVMETHOD_END macro defined in sys/bus.h instead of {0, 0} sentinel on device_method_t arrays

Reviewed by: cognet
Approved by: cognet

fix whitespace

add Roel's copyright as he did the initial version

honor any interface width (e.g. setup by the bus shim) and don't probe;
this is needed for the moment to workaround bus shim issues