imx: support i.MX8QM MEK board

Add i.MX8QM MEK board support.
Included a basic dts, enabled SPL FIT

Boot log as below:
U-Boot SPL 2019.01-rc1-00029-gf002213219 (Dec 24 2018 - 10:28:30 +0800)
Normal Boot
Trying to boot from MMC2_2

U-Boot 2019.01-rc1-00029-gf002213219 (Dec 24 2018 - 10:28:30 +0800)

CPU:   NXP i.MX8QM RevB A53 at 142933 MHz

Model: Freescale i.MX8QM MEK
Board: iMX8QM MEK
Build: SCFW 9330215b
Boot:  SD1
DRAM:  6 GiB
MMC:   FSL_SDHC: 0, FSL_SDHC: 1
Loading Environment from MMC... *** Warning - bad CRC, using default environment

In:    serial@5a060000
Out:   serial@5a060000
Err:   serial@5a060000
Net:
Error: ethernet@5b040000 address not set.
eth-1: ethernet@5b040000
Hit any key to stop autoboot:  0

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/board/freescale/imx8qm_mek/imximage.cfg b/board/freescale/imx8qm_mek/imximage.cfg
new file mode 100644
index 0000000..7dc6b93
--- /dev/null
+++ b/board/freescale/imx8qm_mek/imximage.cfg
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2018 NXP
+ */
+
+#define __ASSEMBLY__
+
+/* Boot from SD, sector size 0x400 */
+BOOT_FROM SD 0x400
+/* SoC type IMX8QM */
+SOC_TYPE IMX8QM
+/* Append seco container image */
+APPEND mx8qm-ahab-container.img
+/* Create the 2nd container */
+CONTAINER
+/* Add scfw image with exec attribute */
+IMAGE SCU mx8qm-mek-scfw-tcm.bin
+/* Add ATF image with exec attribute */
+IMAGE A35 spl/u-boot-spl.bin 0x00100000