aspeed: Add support for the fp5280g2-bmc board

The fp5280g2-bmc is supported by OpenBMC, It's
based on the following device tree

https://github.com/openbmc/linux/blob/dev-5.10/arch/arm/boot/dts/aspeed-bmc-inspur-fp5280g2.dts



Signed-off-by: John Wang <wangzhiqiang02@inspur.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20211014064548.934799-1-wangzhiqiang02@inspur.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>