system-arm: Add ITS node in platforms/vexpress_gem5_v2_base.dtsi

This is aligning sources with DTB autogeneration

Change-Id: Icf369eb85719c91da770398b45645d8b03d8abf3
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20982
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

dev-arm,system-arm: missing GICv3 ranges property

This patch adds the device tree "ranges" property to GICv3 for
the VExpress_GEM5_V2 platform. It is also included in the GICv3 DTB
auto generation.
This allows the GICv3 ITS to be specified in the device tree.

Change-Id: I00e1bb0fd45521e34820c0a23ddf047afec7aa4c
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20255
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

system-arm: Add irq for hypervisor timer in device tree

ARM fast model CPU cannot get timer interrupts without this IRQ setting
in the device tree.

Change-Id: I084c475c04285f4f40eb38a80ddd038207e4764f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19650
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

dev-arm: Limit number of max PE in GICv3 to 128

This is needed since there is a problem in the memory layout of
VExpress_GEM5_V2 as it is: having 256KB pages is creating overlapping
regions when reserving space for 256 PEs.

GICv3 redistributors: 0x2c010000 - 0x30010000
PCI regions: 0x30000000 - 0x40000000

We fix this by cutting down the number of supported PEs to 128

Change-Id: I6e87f66a6150a441ccba298662b4548a4972dc40
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/18392
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

system-arm: Add device tree for new VExpress GEM5_V2 platform

Change-Id: Ifc2b91afe5b88a656b4ed1c64ab6cca97f082034
Reviewed-on: https://gem5-review.googlesource.com/c/14275
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>