Add the missing EOI broadcast from local APIC to the IOAPICs on
completion of level-triggered IRQs. This ensures that a still asserted
IRQ source properly re-triggers an APIC IRQ.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>