kern: refactor init (kill identity map, merge cpu on logic)

libraries/libmesosphere/include/mesosphere/board/nintendo/nx/kern_k_system_control.hpp

@@ -25,12 +25,15 @@ namespace ams::kern::board::nintendo::nx {
             static constexpr size_t SecureAppletMemorySize = 4_MB;
         public:
             class Init : public KSystemControlBase::Init {
+                private:
+                    friend class KSystemControlBase::Init;
+                private:
+                    static void CpuOnImpl(u64 core_id, uintptr_t entrypoint, uintptr_t arg);
                 public:
                     /* Initialization. */
                     static size_t GetRealMemorySize();
                     static size_t GetIntendedMemorySize();
                     static bool ShouldIncreaseThreadResourceLimit();
-                    static void CpuOn(u64 core_id, uintptr_t entrypoint, uintptr_t arg);
                     static size_t GetApplicationPoolSize();
                     static size_t GetAppletPoolSize();
                     static size_t GetMinimumNonSecureSystemPoolSize();