KVM: EVENTFD: Remove inclusion of irq.h

Commit c77dcacb (KVM: Move more code under CONFIG_HAVE_KVM_IRQFD) added
functionality that depends on definitions in ioapic.h when
__KVM_HAVE_IOAPIC is defined.

At the same time, kvm-arm commit 0ba09511 (KVM: EVENTFD: remove inclusion
of irq.h) removed the inclusion of irq.h, an architecture-specific header
that is not present on ARM but which happened to include ioapic.h on x86.

Include ioapic.h directly in eventfd.c if __KVM_HAVE_IOAPIC is defined.
This fixes x86 and lets ARM use eventfd.c.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

virt/kvm/eventfd.c

@@ -36,7 +36,9 @@
 #include <linux/seqlock.h>
 #include <trace/events/kvm.h>
 
-#include "irq.h"
+#ifdef __KVM_HAVE_IOAPIC
+#include "ioapic.h"
+#endif
 #include "iodev.h"
 
 #ifdef CONFIG_HAVE_KVM_IRQFD