misc: imx: S400_API: Move S400 MU and API to a common place

Since iMX9 uses S401 which shares the API with iMX8ULP. So move S400
MU driver and API to a common place and selected by CONFIG_IMX_SENTINEL

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/arch/arm/mach-imx/imx8ulp/rdc.c b/arch/arm/mach-imx/imx8ulp/rdc.c
index e2eca06..cc47079 100644
--- a/arch/arm/mach-imx/imx8ulp/rdc.c
+++ b/arch/arm/mach-imx/imx8ulp/rdc.c
@@ -8,8 +8,8 @@
 #include <asm/types.h>
 #include <asm/arch/imx-regs.h>
 #include <asm/arch/sys_proto.h>
-#include <asm/arch/mu_hal.h>
-#include <asm/arch/s400_api.h>
+#include <asm/mach-imx/mu_hal.h>
+#include <asm/mach-imx/s400_api.h>
 #include <asm/arch/rdc.h>
 #include <div64.h>