soc: arm: nxp_imx: Add i.MX8MQ SoC support

Add SoC support for the NXP i.MX8MQ series MIMX8MQ6 SoC. This SoC
has a quad Cortex-A53 cluster and a single core Cortex-M4 core. Zephyr
support is added to the Cortex-M4 core for running at 266MHz.

More information about the SoC can be found here: https://www.nxp.com/products/processors-and-microcontrollers/arm-processors/i-mx-applications-processors/i-mx-8-processors/i-mx-8m-family-armcortex-a53-cortex-m4-audio-voice-video:i.MX8M



Signed-off-by: Kwon Tae-young <tykwon@m2i.co.kr>