This is based on Lucas' patch sent as "[PATCH v2 4/4] clk: imx: add
clock driver for i.MX8MQ CCM" to the mailing list.

It will likely need some rework before it is finally merged, so apply
the reworks here before merging into barebox.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
[andrew.smirnov@gmail.com: Fix pll type for IMX8MQ_VIDEO2_PLL1]
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>