To support the ast2600's four MACs allow SoCs to specify the number
they have, and create that many.
Signed-off-by: NJoel Stanley <joel@jms.id.au>
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Message-id: 20190925143248.10000-22-clg@kaod.org
[clg: - included a check on sc->macs_num when realizing the macs
      - included interrupt definitions for the AST2600 ]
Signed-off-by: NCédric Le Goater <clg@kaod.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>