Added code to check if the Generic Timer Block Structure's frame number provided by the platform repository is within the allowed range (0-7). References: - ACPI 6.2 Errata A, Table 5-122, September 2017 Signed-off-by: Krzysztof Koch <krzysztof.koch@arm.com> Reviewed-by: Alexei Fedorov <Alexei.Fedorov@arm.com> Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>