Kernel: Rename Kernel/VM/ to Kernel/Memory/

This directory isn't just about virtual memory, it's about all kinds
of memory management.

Kernel/Memory/PageFaultResponse.h

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+namespace Kernel {
+
+enum class PageFaultResponse {
+    ShouldCrash,
+    OutOfMemory,
+    Continue,
+};
+
+}