Currently we reset the KVM interrupt line on initializing the 8250
serial device emulation.
For ARM this creates a problem where we use the in-kernel IRQ chip
before having fully initialized it. But with the new kernel interface
we cannot finish the GIC initialization before we know the number of
used IRQs, so we have to wait until all devices have been created and
initialized.
Since the in-kernel GIC emulation resets the IRQ line anyway and also
QEMU gets away without resetting it, the easiest solution is to drop
the IRQ line reset.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>