ISA v3.0 radix guest execution has a quirk in AIL behaviour such that
the LPCR[AIL] value can apply to hypervisor interrupts.

This affects machines that emulate HV=1 mode (i.e., powernv9).

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Message-Id: <20210415054227.1793812-2-npiggin@gmail.com>
Reviewed-by: Fabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>