drivers: imx: Add separate config option for IMX drivers

Future i.MX platforms will use this config option
to compile NXP specific drivers.

Signed-off-by: Daniel Baluta <daniel.baluta@nxp.com>

src/drivers/CMakeLists.txt

@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
-if(CONFIG_IMX8)
+if(CONFIG_IMX)
 	add_subdirectory(imx)
 endif()
 

src/platform/Kconfig

@@ -167,6 +167,7 @@ config IMX8
 	select HOST_PTABLE
 	select DUMMY_DMA
 	select WAITI_DELAY
+	select IMX
 	help
 	  Select if your target platform is imx8-compatible
 
@@ -179,6 +180,13 @@ config INTEL
 	  This has to be selected for every Intel platform.
 	  It enables Intel platforms-specific features.
 
+config IMX
+	bool
+	default n
+	help
+	  This has to be selected for every i.MX NXP platform.
+	  It enables NXP platforms-specific features.
+
 config CAVS
 	bool
 	default n