vmd(8): remove toggling interrupt line on vcpu in vcpu run loop

vmd(8): remove toggling interrupt line on vcpu in vcpu run loop

We toggle the interrupt "line" on the vcpu when we assert or deassert
irq on the pic in either the vcpu thread (emulating some devices)
or on the device event thread (mostly handling reading available
data). Having it in the vcpu run loop here just results in another
ioctl(2) call before the one for re-entering the guest cpu.

Removing it shows no noticeable behavioral change in existing guests.

ok mlarkin@