Support for AMD Seattle silicon revision A0 is no longer relevant,
since we no longer have a driver for the network controller, and
the PCIe on these boards was very unreliable. So drop the DTS
description of the A0 version of the overdrive board.
Signed-off-by: NArd Biesheuvel <ardb@kernel.org>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>