pstate_read/write ignores nRW field that is kept in env->aarch64

[ivan.i.kulagin]

Hello!
Could you please explain me why in pstate_read and pstate_write
the nRW bit is ignored?
The comment in CPUState says that nRW (also known as M[4]) is kept,
inverted, in env->aarch64,
but the value returned by pstate_read doesn't contain this bit.

static inline uint32_t pstate_read(CPUARMState *env)
{
    int ZF;
    ZF = (env->ZF == 0);
    return (env->NF & 0x80000000) | (ZF << 30)
        | (env->CF << 29) | ((env->VF & 0x80000000) >> 3)
        | env->pstate | env->daif | (env->btype << 10);
}


Best regards, Ivan.