imx: Add support for Ronetix's iMX7-CM board

Console boot log:

U-Boot SPL 2021.04-00836-ga6232e065d-dirty (Apr 16 2021 - 15:16:35 +0200)
Trying to boot from MMC1

U-Boot 2021.04-00836-ga6232e065d-dirty (Apr 16 2021 - 15:16:35 +0200)

CPU:   Freescale i.MX7D rev1.3 1000 MHz (running at 792 MHz)
CPU:   Commercial temperature grade (0C to 95C) at 44C
Reset cause: POR
Model: Ronetix iMX7-CM Board
Board: iMX7-CM
DRAM:  512 MiB
PMIC:  PFUZE3000 DEV_ID=0x30 REV_ID=0x11
MMC:   FSL_SDHC: 0, FSL_SDHC: 2
Loading Environment from MMC... OK
In:    serial
Out:   serial
Err:   serial
Net:
Warning: ethernet@30be0000 (eth0) using random MAC address - fe:be:37:01:5a:3f
eth0: ethernet@30be0000
Hit any key to stop autoboot:  0

Signed-off-by: Ilko Iliev <iliev@ronetix.at>
diff --git a/board/ronetix/imx7-cm/Kconfig b/board/ronetix/imx7-cm/Kconfig
new file mode 100644
index 0000000..a4bc48f
--- /dev/null
+++ b/board/ronetix/imx7-cm/Kconfig
@@ -0,0 +1,15 @@
+if TARGET_IMX7_CM
+
+config SYS_BOARD
+	default "imx7-cm"
+
+config SYS_VENDOR
+	default "ronetix"
+
+config SYS_SOC
+	default "mx7"
+
+config SYS_CONFIG_NAME
+	default "imx7-cm"
+
+endif