[RESEND PATCH v5 4/7] mfd: cros_ec_dev: Register cros-ec-rtc driver as a subdevice.

Check whether this EC instance has RTC host command support and instatiate the RTC driver as a subdevice in such case. Signed-off-by: Enric Balletbo i Serra Reviewed-by: Gwendal Grignou Reviewed-by: Andy Shevchenko

[RESEND PATCH v5 4/7] mfd: cros_ec_dev: Register cros-ec-rtc driver as a subdevice.

Check whether this EC instance has RTC host command support and instatiate the RTC driver as a subdevice in such case. Signed-off-by: Enric Balletbo i Serra Reviewed-by: Gwendal Grignou Reviewed-by: Andy Shevchenko --- Changes in v5: - [4/8] For mfd_cell struct use one line and no need for