Appended patch fixes the "APIC error on CPUX: 00(40)" observed during bootup.
From SDM Vol-3A "Valid Interrupt Vectors" section:
"When an illegal vector value (0-15) is written to an LVT entry
and the delivery mode is Fixed, the APIC may signal an illegal
vector error, with out regard to whether the mask bit is set
or whether an interrupt is actually seen on input."