arm: imx: add i.MX8ULP basic Kconfig option

Add i.MX8ULP related basic Kconfig option, which will be used later.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 3a745ce..e935c60b 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -801,6 +801,15 @@
 	select SUPPORT_SPL
 	imply CMD_DM
 
+config ARCH_IMX8ULP
+	bool "NXP i.MX8ULP platform"
+	select ARM64
+	select DM
+	select OF_CONTROL
+	select SUPPORT_SPL
+	select GPIO_EXTRA_HEADER
+	imply CMD_DM
+
 config ARCH_IMXRT
 	bool "NXP i.MXRT platform"
 	select CPU_V7M
@@ -1971,6 +1980,8 @@
 
 source "arch/arm/mach-imx/imx8m/Kconfig"
 
+source "arch/arm/mach-imx/imx8ulp/Kconfig"
+
 source "arch/arm/mach-imx/imxrt/Kconfig"
 
 source "arch/arm/mach-imx/mxs/Kconfig"