yuzu: Move compatibility list specifics to their own source files

Lets us keep the generic portions of the compatibility list code
together, and allows us to introduce a type alias that makes it so we
don't need to type out a very long type declaration anymore, making the
immediate readability of some code better.

src/citra_qt/compatibility_list.h

@@ -0,0 +1,17 @@
+// Copyright 2018 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <string>
+#include <unordered_map>
+
+#include <QString>
+
+#include "common/common_types.h"
+
+using CompatibilityList = std::unordered_map<std::string, std::pair<QString, QString>>;
+
+CompatibilityList::const_iterator FindMatchingCompatibilityEntry(
+    const CompatibilityList& compatibility_list, u64 program_id);