irqchip/gic-v3-its: Check that all RDs have the same property table

If booting with LPIs enabled, all the redistributors must have the
exact same property table. No ifs, no buts.

Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Tested-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: Lei Zhang <zhang.lei@jp.fujitsu.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>