interconnect: imx: Add platform driver for imx8mq

Add a platform driver for the i.MX8MQ SoC describing bus topology,
based on internal documentation.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Tested-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Link: https://lore.kernel.org/r/864310d1f2599c3bd621e70b77028a6e89f6410e.1586174566.git.leonard.crestez@nxp.com
Signed-off-by: Georgi Djakov <georgi.djakov@linaro.org>