kernel/thread: Change owner_process to std::weak_ptr (#5325)

* kernel/thread: Change owner_process to std::weak_ptr

Previously this leaked almost all kernel objects. In short, Threads own Processes which own HandleTables which own maps of Objects which include Threads.

Changing this to weak_ptr at least got the camera interfaces to destruct properly. Did not really check the other objects though, and I think there are probably more leaks.

* hle/kernel: Lock certain objects while deserializing

When deserializing other kernel objects, these objects (`MemoryRegion`s and `VMManager`s) can possibly get modified. To avoid inconsistent state caused by destructor side-effects, we may as well simply lock them until loading is fully completed.

* Fix silly typo

Somehow this didn't break?!

src/core/hle/kernel/vm_manager.h

@@ -212,6 +212,11 @@ public:
     /// is scheduled.
     std::shared_ptr<Memory::PageTable> page_table;
 
+    /**
+     * Unlock the VMManager. Used after loading is completed.
+     */
+    void Unlock();
+
 private:
     using VMAIter = decltype(vma_map)::iterator;
 
@@ -250,10 +255,17 @@ private:
 
     Memory::MemorySystem& memory;
 
+    // When locked, ChangeMemoryState calls will be ignored, other modification calls will hit an
+    // assert. VMManager locks itself after deserialization.
+    bool is_locked{};
+
     template <class Archive>
     void serialize(Archive& ar, const unsigned int) {
         ar& vma_map;
         ar& page_table;
+        if (Archive::is_loading::value) {
+            is_locked = true;
+        }
     }
     friend class boost::serialization::access;
 };