imx: add IMX8MQ kconfig entry

Add IMX8MQ kconfig entry, preparing support IMX8MM

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/imx8m/Kconfig b/arch/arm/mach-imx/imx8m/Kconfig
index 317dee9..9c48787 100644
--- a/arch/arm/mach-imx/imx8m/Kconfig
+++ b/arch/arm/mach-imx/imx8m/Kconfig
@@ -4,6 +4,10 @@
 	bool
 	select ROM_UNIFIED_SECTIONS
 
+config IMX8MQ
+	bool
+	select IMX8M
+
 config SYS_SOC
 	default "imx8m"
 
@@ -13,7 +17,7 @@
 
 config TARGET_IMX8MQ_EVK
 	bool "imx8mq_evk"
-	select IMX8M
+	select IMX8MQ
 	select IMX8M_LPDDR4
 
 endchoice