In v8.1M a REVIDR register is defined, which is at address 0xe00ecfc
and is a read-only IMPDEF register providing implementation specific
minor revision information, like the v8A REVIDR_EL1. Implement this.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201119215617.29887-19-peter.maydell@linaro.org