drm/xe: Use symbol namespace for kunit tests

Instead of simply using EXPORT_SYMBOL() to export the functions needed
in xe.ko to be be called across modules, use EXPORT_SYMBOL_IF_KUNIT()
which will export the symbol under the EXPORTED_FOR_KUNIT_TESTING
namespace.

This avoids accidentally "leaking" these functions and letting them be
called from outside the kunit tests. If these functiosn are accidentally
called from another module, they receive a modpost error like below:

	ERROR: modpost: module XXXXXXX uses symbol
	xe_ccs_migrate_kunit from namespace EXPORTED_FOR_KUNIT_TESTING,
	but does not import it.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/20230401085151.1786204-4-lucas.demarchi@intel.com

drivers/gpu/drm/xe/tests/xe_bo.c

@@ -4,6 +4,7 @@
  */
 
 #include <kunit/test.h>
+#include <kunit/visibility.h>
 
 #include "tests/xe_bo_test.h"
 #include "tests/xe_pci_test.h"
@@ -166,7 +167,7 @@ void xe_ccs_migrate_kunit(struct kunit *test)
 {
 	xe_call_for_each_device(ccs_test_run_device);
 }
-EXPORT_SYMBOL(xe_ccs_migrate_kunit);
+EXPORT_SYMBOL_IF_KUNIT(xe_ccs_migrate_kunit);
 
 static int evict_test_run_gt(struct xe_device *xe, struct xe_gt *gt, struct kunit *test)
 {
@@ -304,4 +305,4 @@ void xe_bo_evict_kunit(struct kunit *test)
 {
 	xe_call_for_each_device(evict_test_run_device);
 }
-EXPORT_SYMBOL(xe_bo_evict_kunit);
+EXPORT_SYMBOL_IF_KUNIT(xe_bo_evict_kunit);

drivers/gpu/drm/xe/tests/xe_bo_test.c

@@ -22,3 +22,4 @@ kunit_test_suite(xe_bo_test_suite);
 
 MODULE_AUTHOR("Intel Corporation");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);

drivers/gpu/drm/xe/tests/xe_dma_buf.c

@@ -4,6 +4,7 @@
  */
 
 #include <kunit/test.h>
+#include <kunit/visibility.h>
 
 #include "tests/xe_dma_buf_test.h"
 #include "tests/xe_pci_test.h"
@@ -259,4 +260,4 @@ void xe_dma_buf_kunit(struct kunit *test)
 {
 	xe_call_for_each_device(dma_buf_run_device);
 }
-EXPORT_SYMBOL(xe_dma_buf_kunit);
+EXPORT_SYMBOL_IF_KUNIT(xe_dma_buf_kunit);

drivers/gpu/drm/xe/tests/xe_dma_buf_test.c

@@ -21,3 +21,4 @@ kunit_test_suite(xe_dma_buf_test_suite);
 
 MODULE_AUTHOR("Intel Corporation");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);

drivers/gpu/drm/xe/tests/xe_migrate.c

@@ -4,6 +4,7 @@
  */
 
 #include <kunit/test.h>
+#include <kunit/visibility.h>
 
 #include "tests/xe_migrate_test.h"
 #include "tests/xe_pci_test.h"
@@ -409,4 +410,4 @@ void xe_migrate_sanity_kunit(struct kunit *test)
 {
 	xe_call_for_each_device(migrate_test_run_device);
 }
-EXPORT_SYMBOL(xe_migrate_sanity_kunit);
+EXPORT_SYMBOL_IF_KUNIT(xe_migrate_sanity_kunit);

drivers/gpu/drm/xe/tests/xe_migrate_test.c

@@ -21,3 +21,4 @@ kunit_test_suite(xe_migrate_test_suite);
 
 MODULE_AUTHOR("Intel Corporation");
 MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(EXPORTED_FOR_KUNIT_TESTING);