If pckbc_xt_translation() fails, do not try to force the keyboard in table

If pckbc_xt_translation() fails, do not try to force the keyboard in table
1; instead, try table 2 first, then 1: some older keyboards, connected to
a castrated 8042, do not know how to talk in table 1 (or worse, will report
they do while they don't).

If automatic translation is not possible, remember which table the keyboard
ended configured in, and convert the scancodes from table 2 to table 1 if
necessary.

ok kettenis@