DynamicLoader+LibELF: Move self-relocation code into a separate file

Userland/Libraries/LibELF/Relocation.h

@@ -0,0 +1,18 @@
+/*
+ * Copyright (c) 2021, Gunnar Beutner <gbeutner@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Concepts.h>
+#include <AK/String.h>
+#include <AK/Vector.h>
+#include <Kernel/VirtualAddress.h>
+
+namespace ELF {
+
+bool perform_relative_relocations(FlatPtr base_address);
+
+}