KVM: arm/arm64: Let vcpu thread modify its own active state

KVM: arm/arm64: Let vcpu thread modify its own active state

BugLink: http://bugs.launchpad.net/bugs/1674288
commit 370a0ec1819990f8e2a93df7cc9c0146980ed45f upstream.

Currently, if a vcpu thread tries to change the active state of an
interrupt which is already on the same vcpu's AP list, it will loop
forever. Since the VGIC mmio handler is called after a vcpu has
already synced back the LR state to the struct vgic_irq, we can just
let it proceed safely.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>