Fix incorrect VdpPictureInfo typedef.

VdpPictureInfo should not be a pointer, otherwise the
VdpDecoderRender function signature asks for a pointer to a pointer.
But it really does expect a pointer directly to e.g. VdpPictureInfoH264.

Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Tested-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Aaron Plattner <aplattner@nvidia.com>