FreeRTOS BeagleBone Black (Sitara am3358) port
Official Cortex A9 port will be amended because Sitara am3358 uses TI INTC interrupt controller. This is registers are changed:
GIC | INTC
ICCPMR | INTC_THRESHOLD ICCIAR | INTC_SIR_IRQ(currently active irq) + INTC_CONTROL(acknowledgement) ICCEOIR | ?
Priority grouping code is removed because INTC doesn't support priority grouping.