ntdll/tests: Fix some string leaks (Valgrind).

dlls/ntdll/tests/file.c

@@ -3662,6 +3662,8 @@ static void test_file_mode(void)
         if (option_tests[i].file_name == &file_name)
             DeleteFileW(dos_file_name);
     }
+
+    pRtlFreeUnicodeString(&file_name);
 }
 
 static void test_query_volume_information_file(void)

dlls/ntdll/tests/reg.c

@@ -2008,6 +2008,8 @@ static void test_RtlCreateRegistryKey(void)
 
     status = pRtlCreateRegistryKey((RTL_REGISTRY_USER+1) | RTL_REGISTRY_OPTIONAL, NULL);
     ok(status == STATUS_INVALID_PARAMETER, "RtlCreateRegistryKey unexpected return value: %08x, expected %08x\n", status, STATUS_INVALID_PARAMETER);
+
+    pRtlFreeUnicodeString(&str);
 }
 
 START_TEST(reg)