CMake: Use precompiled headers

src/core/precompiled_headers.h

@@ -0,0 +1,14 @@
+// SPDX-FileCopyrightText: 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include <algorithm>
+#include <chrono>
+#include <memory>
+
+#include <boost/container/flat_map.hpp> // used by service.h which is heavily included
+#include <boost/intrusive/rbtree.hpp>   // used by k_auto_object.h which is heavily included
+#include <fmt/format.h>
+
+#include "common/assert.h"