dev-arm: Adjust off_chip ranges in VExpress_GEM5 platform

dev-arm: Adjust off_chip ranges in VExpress_GEM5 platform

This is need after commit b4c9996d894118be04cdf4ed793b35a1d5001942
which makes the AddrRange end address non inclusive.

Change-Id: I859b84f6a91107815236b67c4596291c78881fe3
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/23003
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>