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/drivers/misc/Kconfig b/drivers/misc/Kconfig
index e839c08..a6da6e2 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -350,6 +350,13 @@
 	  To compile this driver as a module, choose M here: the module
 	  will be called npcm_otp.
 
+config IMX_SENTINEL
+	bool "Enable i.MX Sentinel MU driver and API"
+	depends on MISC && (ARCH_IMX9 || ARCH_IMX8ULP)
+	help
+	  If you say Y here to enable Message Unit driver to work with
+	  Sentinel core on some NXP i.MX processors.
+
 config NUVOTON_NCT6102D
 	bool "Enable Nuvoton NCT6102D Super I/O driver"
 	help