arm/arm64: ITS: INT functional tests

Triggers LPIs through the INT command.

the test checks the LPI hits the right CPU and triggers
the right LPI intid, ie. the translation is correct.

Updates to the config table also are tested, along with inv
and invall commands.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Andrew Jones <drjones@redhat.com>