Add a new memory region in system address space where DMA address space
definition (the 'translation table') belongs, so we can update on the fly
the DMA address space.

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>