smbus: Move smbus_utils.h from includes to driver area

Move smbus_utils.h header from generic includes to the driver's area
in order to have in include/zephyr/drivers only smbus.h header.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>

drivers/smbus/intel_pch_smbus.c

@@ -21,7 +21,7 @@
 #include <zephyr/logging/log.h>
 LOG_MODULE_REGISTER(intel_pch, CONFIG_SMBUS_LOG_LEVEL);
 
-#include <zephyr/drivers/smbus_utils.h>
+#include "smbus_utils.h"
 #include "intel_pch_smbus.h"
 
 /**

tests/drivers/smbus/smbus_api/CMakeLists.txt

@@ -6,6 +6,7 @@ if(BOARD STREQUAL qemu_x86_64)
 	LIST(APPEND QEMU_EXTRA_FLAGS -machine q35)
 endif()
 
+target_include_directories(app PRIVATE ${ZEPHYR_BASE}/drivers/smbus)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(smbus_api)
 

tests/drivers/smbus/smbus_api/src/test_smbus.c

@@ -11,7 +11,8 @@
 #include <zephyr/kernel.h>
 #include <zephyr/ztest.h>
 #include <zephyr/drivers/smbus.h>
-#include <zephyr/drivers/smbus_utils.h>
+
+#include <smbus_utils.h>
 
 BUILD_ASSERT(DT_NODE_HAS_STATUS(DT_NODELABEL(smbus0), okay),
 	     "SMBus node is disabled!");