The McaIntrCfg register (MSRC000_0410), previously known as CU_DEFER_ERR,
is used on SMCA systems to set the LVT offset for the Threshold and
Deferred error interrupts.
This register was used on non-SMCA systems to also set the Deferred
interrupt type in bits 2:1. However, these bits are reserved on SMCA
systems.