MLK-16804-01 driver: clocksource: Add nxp system counter broadcast timer

On NXP i.MX8MQ SOC, it has system counter module for ARM
generic timer implementation. In this system counter module
it also has compare frame module to provide timer support.
So we can use it as an alternative clockevent device for
broadcast timer purpose when CPU core enter power down state
with local timer stopped.

Signed-off-by: Bai Ping <ping.bai@nxp.com>
Reviewed-by: Anson Huang <anson.huang@nxp.com>
(cherry picked from commit f69eab1d)