Update Armada 8k drivers to cover newly imported DT and latest changes
in simple multifunction driver.

• follow interrupt changes in DT. Split old ICU driver to function oriented parts and add drivers for newly defined parts (system error interrupts).
• Many drivers are children of simple multifunction driver. But after r349596 simple MF driver doesn't longer exports memory resources, and all children must use syscon interface to access their registers. Adapt affected drivers to this fact.

MFC after: 3 weeks