aspeed/smc: fix default read value

0xFFFFFFFF should be returned for non implemented registers.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Message-id: 20190124140519.13838-2-clg@kaod.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
1 file changed