vSMP can route interrupts more optimally based on internal
knowledge the OS does not have. In order to support this
optimization, all CPUs must be able to handle all possible
IOAPIC interrupts.

Fix this by setting the vector allocation domain for all CPUs
and by enabling this feature in vSMP.
Signed-off-by: NRavikiran Thirumalai <kiran.thirumalai@gmail.com>
Signed-off-by: NShai Fultheim <shai@scalemp.com>
[ Rebased, simplified, and reworded the commit message. ]
Signed-off-by: NIdo Yariv <ido@wizery.com>
Signed-off-by: NIngo Molnar <mingo@kernel.org>