firmware: arm_scmi: imx: Support retrieving MISC protocol configuration info

firmware: arm_scmi: imx: Support retrieving MISC protocol configuration info

The MISC protocol can provide System Manager (SM) configuration
information, including platform identifiers and board-specific
attributes. Add support to retrieve this information during protocol
initialization.

If the firmware does not implement the CFG_INFO command, handle
-EOPNOTSUPP gracefully and continue without failing init.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Message-Id: <20250904-sm-misc-api-v1-v4-3-0bf10eaabdf1@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>