imx: Add support for i.MX8MN Beacon EmbeddedWorks devkit.

Beacon EmbeddedWorks is releasing a devkit based on the i.MX8M
Nano SoC consisting of baseboard + SOM.

The kit is based on the same design as the Beacon dev kit with
the i.MX8M Mini.

Signed-off-by: Adam Ford <aford173@gmail.com>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/imx8m/Kconfig b/arch/arm/mach-imx/imx8m/Kconfig
index 78e4fb6..c455f7b 100644
--- a/arch/arm/mach-imx/imx8m/Kconfig
+++ b/arch/arm/mach-imx/imx8m/Kconfig
@@ -72,6 +72,12 @@
 	select SUPPORT_SPL
 	select IMX8M_LPDDR4
 
+config TARGET_IMX8MN_BEACON
+	bool "imx8mn Beacon Embedded devkit"
+	select IMX8MN
+	select SUPPORT_SPL
+	select IMX8M_LPDDR4
+
 config TARGET_PHYCORE_IMX8MM
 	bool "PHYTEC PHYCORE i.MX8MM"
 	select IMX8MM
@@ -93,6 +99,7 @@
 source "board/technexion/pico-imx8mq/Kconfig"
 source "board/toradex/verdin-imx8mm/Kconfig"
 source "board/beacon/imx8mm/Kconfig"
+source "board/beacon/imx8mn/Kconfig"
 source "board/phytec/phycore_imx8mm/Kconfig"
 source "board/phytec/phycore_imx8mp/Kconfig"