Move most arch/i386 files to arch/x86, and adjust the contents of the
Makefiles and the include/bits/*.h headers to reflect the new
locations.

This patch makes no substantive code changes, as can be seen using a
rename-aware diff (e.g. "git show -M5").

This patch does not make the pcbios platform functional for x86_64; it
merely allows it to compile without errors.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Relicense files for which I am the sole author (as identified by
util/relicense.pl).

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Signed-off-by: Michael Brown <mcb30@ipxe.org>

Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

Add FILE_LICENCE declarations to almost all files that make up the
various standard builds of gPXE.

We now have two implementations for the timer API: one using the
time-of-day counter at 40:70 and one using RDTSC.  Both make use of
timer2_udelay().