ArmCpuInfo needs to be able to read ID_AA64ISAR2_EL1 system register. Older toolchains do not know it. Same solution as one for QEMU: https://www.mail-archive.com/qemu-devel@nongnu.org/msg929586.html Signed-off-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org> Reviewed-by: Leif Lindholm <quic_llindhol@quicinc.com>