Add the new GICv4 ITS command definitions, most of them, being
defined in terms of their physical counterparts.
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Reviewed-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>