This patch adds support for split IRQ chip mode. When
KVM_CAP_SPLIT_IRQCHIP is enabled:
1.) The PIC, PIT, and IOAPIC are implemented in userspace while
the LAPIC is implemented by KVM.
2.) The software IOAPIC delivers interrupts to the KVM LAPIC via
kvm_set_irq. Interrupt delivery is configured via the MSI routing
table, for which routes are reserved in target-i386/kvm.c then
configured in hw/intc/ioapic.c
3.) KVM delivers IOAPIC EOIs via a new exit KVM_EXIT_IOAPIC_EOI,
which is handled in target-i386/kvm.c and relayed to the software
IOAPIC via ioapic_eoi_broadcast.
Signed-off-by: Matt Gingell <gingell@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>