The following variants
* GICv1 with Security Extensions,
* GICv2 without Security Extensions, or
* within Secure processor mode
have the ability to assign group 0 or 1 to individual interrupts. Group
0 interrupts can be configured to raise an FIQ exception. This enables
the use of NMIs with respect to RTEMS.
BSPs can enable this feature with the BSP_ARM_GIC_ENABLE_FIQ_FOR_GROUP_0
define. Use arm_gic_irq_set_group() to change the group of an
interrupt (default group is 1, if BSP_ARM_GIC_ENABLE_FIQ_FOR_GROUP_0 is
defined).
