Support of 0.5% down-spread is required for DisplayPort Specification
Version 1.1 Sink.
Signed-off-by: NEnric Balletbo i Serra <enric.balletbo@collabora.com>
[treding@nvidia.com: rename to DP_MAX_DOWNSPREAD_0_5]
Signed-off-by: NThierry Reding <treding@nvidia.com>