KVM: vgic: add virt-capable compatible strings

Several dts only list "arm,cortex-a7-gic" or "arm,gic-400" in their GIC
compatible list, and while this is correct (and supported by the GIC
driver), KVM will fail to detect that it can support these cases.

This patch adds the missing strings to the VGIC code. The of_device_id
entries are padded to keep the probe function data aligned.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michal Simek <monstr@monstr.eu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>