kbd: complete dead keys definitions

This completes dead keys definitions for internationalization
completeness on the console.  The representatives have been chosen
coherently with libx11 compose sequences, which avoid symetry conflicts
(e.g. there is U with caron, but no c with breve).

Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>