imx: add basic i.MX9 support

Add i.MX9 Kconfig and basic files for the new SoC

Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/imx9/Kconfig b/arch/arm/mach-imx/imx9/Kconfig
new file mode 100644
index 0000000..ff254c2
--- /dev/null
+++ b/arch/arm/mach-imx/imx9/Kconfig
@@ -0,0 +1,16 @@
+if ARCH_IMX9
+
+config IMX9
+	bool
+	select HAS_CAAM
+	select ROM_UNIFIED_SECTIONS
+
+config IMX93
+	bool
+	select IMX9
+	select ARMV8_SPL_EXCEPTION_VECTORS
+
+config SYS_SOC
+	default "imx9"
+
+endif