Bring CoherentDmaLib in line with ArmDmaLib, and add support for defining a static offset between the host's and the bus master's view of memory. Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>