hw/arm: Add support for kudo-bmc board.

kudo-bmc is a board supported by OpenBMC.
https://github.com/openbmc/openbmc/tree/master/meta-fii/meta-kudo



Since v1:
- hyphenated Cortex-A9

Tested: Booted kudo firmware.
Signed-off-by: Chris Rauer <crauer@google.com>
Reviewed-by: Patrick Venture <venture@google.com>
Message-id: 20210907223234.1165705-1-crauer@google.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>