I want to get to the point where any header in include/ reflects a
standard user-level header (e.g. a POSIX header), while everything that's
specific to gPXE lives in include/gpxe/.  Headers that reflect a Linux
header (e.g. if_ether.h) should also be in include/gpxe/, with the same
name as the Linux header and, preferably, the same names used for the
definitions.

Remove compiler.h defines from osdep.h

thinks they are.
Other bus drivers modified for consistency.

(Detected using "make symcheck" :)

changes.

initial device, and will also allow for e.g. a device menu to be presented
to the user.

have different probe functions.

link time to accommodate whatever bus objects are included.

*other* than the main boot device.