-optionally, use Martin's direct hardware access to serial lines
-optionally, new console autoselection method: select serial console
if a character is seen within 1 second
-move awaitkey() here, it can be shared by different bootloaders and
it is used by console autoselection
-collect information about console selection in a "bootinfo" defined
structure, for passing to the kernel
little hacking by me. This isn't strictly identical to his 920312
release -- I've hacked it a bit -- but since we are taking over change
control it doesn't matter much.
