Support for NXP's i.MX8QX SoC

NXP's i.MX8QX is an ARMv8 SoC with 4 Cortex-A35 cores and
system controller (Cortex-M4) inside, documentation can
be found in below link:

https://www.nxp.com/products/processors-and-microcontrollers/
applications-processors/i.mx-applications-processors/i.mx-8-processors:IMX8-SERIES

This patch adds support for booting up SMP linux kernel (v4.9).

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
diff --git a/maintainers.rst b/maintainers.rst
index 2217cbe..195f1f3 100644
--- a/maintainers.rst
+++ b/maintainers.rst
@@ -92,6 +92,16 @@
 -  docs/plat/ls1043a.rst
 -  plat/layerscape/\*
 
+NXP i.MX 8 platform sub-maintainer
+--------------------------------------
+
+Anson Huang (Anson.Huang@nxp.com, `Anson-Huang`_)
+
+Files:
+
+-  docs/plat/imx8.rst
+-  plat/imx/\*
+
 Raspberry Pi 3 platform sub-maintainer
 --------------------------------------