KS869x: add new target
This patch adds Micrel's KS869x target. The configuration was taken from
http://www.mmnt.net/db/0/0/www.micrel.com/ethernet/8695 - Micrel's
FTP server i.e. their OpenOCD 7.0 package.
The only change compared to the original file is the removal of
reset configuration, as it belongs to the board configuration.
Signed-off-by: Yegor Yefremov <email@example.com>