Add support for extended descriptors with optional 64bit
addressing and timestamping. QEMU will not yet provide
timestamps (always leaving the valid timestamp bit as zero).
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Message-id: 20181011021931.4249-6-edgar.iglesias@gmail.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>