hw/rtc/mc146818rtc: Pass MC146818RtcState instead of ISADevice argument

rtc_get_memory() and rtc_set_memory() methods can not take any
TYPE_ISA_DEVICE object. They expect a TYPE_MC146818_RTC one.

Simplify the API by passing a MC146818RtcState.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230210233116.80311-3-philmd@linaro.org>
6 files changed