system-arm: bigLITTLE with VExpress_GEM5_V2 in dtb
system-arm: bigLITTLE with VExpress_GEM5_V2 in dtb

This patch adds targets in the device tree Makefile for using
bigLITTLE DTS with VExpress_GEM5_V2 platform.

Change-Id: I7a424a36c78a24b96224526aa112ac5d060f790b
Reviewed-by: Giacomo Travaglini <8eef13a4f970e2e9372c8d26ad0737b760f99c02@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24083
Reviewed-by: Ciro Santilli <f9f94c17362144ef13d3dda5cd3efb8325112763@arm.com>
Maintainer: Giacomo Travaglini <8eef13a4f970e2e9372c8d26ad0737b760f99c02@arm.com>
Tested-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>

gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5,gem5/gem5