The ASRock Rack ALTRAD8UD-1L2T AMI AptioV UEFI firmware has 63
areas of memory with RuntimeServicesData or RuntimeServicesCode.
Increase the values of MAX_HWCNT and MAX_EXCNT to 256 to avoid
overflowing the arrays (resulting in the boot hanging) when booting on
this system or any others which have very fragmented memory maps.