pub fn ready(&mut self) -> nb::Result<(), Infallible> {
        if self.regs().clean().read().clean().bit_is_clear() {
            return Err(nb::Error::WouldBlock);
        }
        Ok(())
    }
After the RSA Accelerator is released from reset, the memory blocks
needs to be initialized, only after that peripheral should be used.
This function would return without an error if the memory is initialized
esp-hal/src/rsa/esp32.rs