rtc: support i.MX95 BBM RTC

rtc: support i.MX95 BBM RTC

The BBM module provides RTC feature. To i.MX95, this module is managed by
System Manager and exported System Control Management Interface(SCMI).
Linux could use i.MX SCMI BBM Extension protocol to use RTC feature.

This driver is to use SCMI interface to get/set RTC.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Message-Id: <20240823-imx95-bbm-misc-v2-v8-6-e600ed9e9271@nxp.com>
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>