I am unable to find any definitive documentation on how Linux keyboard
symbols work.  In the absence of any documentation, I'm going to
assume that unexpected keysyms are harmless and should be ignored.

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

The "us" keyboard layout contains a mapping for keycode 86 (which
seems not to correspond to any physical key on many US keyboards) to
the ASCII character '<'.  This mapping causes conflicts with the
mapping for keycode 51, which also maps (with shift) to '<'.

Change the keyboard mapping generator to choose the lowest keycode for
each ASCII character as indicating the relevant mapping to use, on the
basis that a lower keycode roughly indicates a "more normal" key.  On
a German keyboard, which has keys for both keycode 51 and keycode 86
present, this causes '<' to be remapped to ';', which is a closer
match to typical user expectations.

Reported-by: Sven Dreyer <sven@dreyer-net.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>

Inspired by LILO's keytab-lilo.pl, genkeymap.pl uses "loadkeys -b" to
obtain a Linux keyboard map, and generates a file keymap_xx.c in
hci/keymap.

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