unittests: tests-ipv6_addr: adapt for optional IPv4 address support

tests/unittests/tests-ipv6_addr/tests-ipv6_addr.c

@@ -862,8 +862,11 @@ static void test_ipv6_addr_to_str__success5(void)
     };
     char result[IPV6_ADDR_MAX_STR_LEN];
 
-    TEST_ASSERT_EQUAL_STRING("::ffff:192.168.0.1",
-                             ipv6_addr_to_str(result, &a, sizeof(result)));
+#ifdef MODULE_IPV4_ADDR
+    TEST_ASSERT_EQUAL_STRING("::ffff:192.168.0.1", ipv6_addr_to_str(result, &a, sizeof(result)));
+#else
+    TEST_ASSERT_EQUAL_STRING("::ffff:c0a8:1", ipv6_addr_to_str(result, &a, sizeof(result)));
+#endif
 }
 
 static void test_ipv6_addr_from_str__one_colon_start(void)
@@ -980,7 +983,11 @@ static void test_ipv6_addr_from_str__success6(void)
     };
     ipv6_addr_t result;
 
+#ifdef MODULE_IPV4_ADDR
     TEST_ASSERT_NOT_NULL(ipv6_addr_from_str(&result, "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255"));
+#else
+    TEST_ASSERT_NOT_NULL(ipv6_addr_from_str(&result, "ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff"));
+#endif
     TEST_ASSERT(ipv6_addr_equal(&a, &result));
 }