update(riscv/iommu): add multi-lvl DDT support

Signed-off-by: Manuel Rodríguez <[email protected]>

Author: malejo97

src/arch/riscv/inc/arch/platform.h

@@ -23,7 +23,6 @@ struct arch_platform {
 
     struct {
         paddr_t base;      // Base address of the IOMMU mmapped IF
-        unsigned mode;     // Overall IOMMU mode (Off, Bypass, DDT-lvl)
         irqid_t fq_irq_id; // Fault Queue IRQ ID (wired)
     } iommu;