service: Migrate global named port map to the KernelCore class

Now that we have a class representing the kernel in some capacity, we
now have a place to put the named port map, so we move it over and get
rid of another piece of global state within the core.

src/core/hle/service/service.h

@@ -6,7 +6,6 @@
 
 #include <cstddef>
 #include <string>
-#include <unordered_map>
 #include <boost/container/flat_map.hpp>
 #include "common/common_types.h"
 #include "core/hle/kernel/hle_ipc.h"
@@ -187,10 +186,4 @@ void Init(std::shared_ptr<SM::ServiceManager>& sm,
 /// Shutdown ServiceManager
 void Shutdown();
 
-/// Map of named ports managed by the kernel, which can be retrieved using the ConnectToPort SVC.
-extern std::unordered_map<std::string, Kernel::SharedPtr<Kernel::ClientPort>> g_kernel_named_ports;
-
-/// Adds a port to the named port table
-void AddNamedPort(std::string name, Kernel::SharedPtr<Kernel::ClientPort> port);
-
 } // namespace Service