tests: posix: test pthread_cleanup_push() / pop()

Add a test for pthread_cleanup_push() and
pthread_cleanup_pop().

Signed-off-by: Christopher Friedt <cfriedt@meta.com>

tests/posix/common/src/pthread.c

@@ -882,3 +882,33 @@ ZTEST(posix_apis, test_pthread_join_detached)
 	/* need to allow this thread to be clean-up by the recycler */
 	k_msleep(500);
 }
+
+static void cleanup_handler(void *arg)
+{
+	bool *boolp = (bool *)arg;
+
+	*boolp = true;
+}
+
+static void *test_pthread_cleanup_entry(void *arg)
+{
+	bool executed[2] = {0};
+
+	pthread_cleanup_push(cleanup_handler, &executed[0]);
+	pthread_cleanup_push(cleanup_handler, &executed[1]);
+	pthread_cleanup_pop(false);
+	pthread_cleanup_pop(true);
+
+	zassert_true(executed[0]);
+	zassert_false(executed[1]);
+
+	return NULL;
+}
+
+ZTEST(posix_apis, test_pthread_cleanup)
+{
+	pthread_t th;
+
+	zassert_ok(pthread_create(&th, NULL, test_pthread_cleanup_entry, NULL));
+	zassert_ok(pthread_join(th, NULL));
+}