target/arm: Apply access checks to neoverse-n1 special registers

target/arm: Apply access checks to neoverse-n1 special registers

Access to many of the special registers is enabled or disabled
by ACTLR_EL[23], which we implement as constant 0, which means
that all writes outside EL3 should trap.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20230811214031.171020-7-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>