kunit: add missing MODULE_DESCRIPTION() macros to core modules

make allmodconfig && make W=1 C=1 reports in lib/kunit:
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/kunit/kunit.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/kunit/kunit-test.o
WARNING: modpost: missing MODULE_DESCRIPTION() in lib/kunit/kunit-example-test.o

Add the missing invocations of the MODULE_DESCRIPTION() macro.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Rae Moar <rmoar@google.com>
Reviewed-by: David Gow <davidgow@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

lib/kunit/kunit-example-test.c

@@ -374,4 +374,5 @@ static struct kunit_suite example_init_test_suite = {
  */
 kunit_test_init_section_suites(&example_init_test_suite);
 
+MODULE_DESCRIPTION("Example KUnit test suite");
 MODULE_LICENSE("GPL v2");

lib/kunit/kunit-test.c

@@ -871,4 +871,5 @@ kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite,
 		  &kunit_current_test_suite, &kunit_device_test_suite,
 		  &kunit_fault_test_suite);
 
+MODULE_DESCRIPTION("KUnit test for core test infrastructure");
 MODULE_LICENSE("GPL v2");

lib/kunit/test.c

@@ -938,4 +938,5 @@ static void __exit kunit_exit(void)
 }
 module_exit(kunit_exit);
 
+MODULE_DESCRIPTION("Base unit test (KUnit) API");
 MODULE_LICENSE("GPL v2");