vm_manager: Amend MemoryState enum members

Amends the MemoryState enum to use the same values like the actual
kernel does. Also provides the necessary operators to operate on them.
This will be necessary in the future for implementing
svcSetMemoryAttribute, as memory block state is checked before applying
the attribute.

src/core/hle/kernel/vm_manager.cpp

@@ -25,14 +25,14 @@ static const char* GetMemoryStateName(MemoryState state) {
         "CodeMutable",      "Heap",
         "Shared",           "Unknown1",
         "ModuleCodeStatic", "ModuleCodeMutable",
-        "IpcBuffer0",       "Mapped",
+        "IpcBuffer0",       "Stack",
         "ThreadLocal",      "TransferMemoryIsolated",
         "TransferMemory",   "ProcessMemory",
         "Unknown2",         "IpcBuffer1",
         "IpcBuffer3",       "KernelStack",
     };
 
-    return names[static_cast<int>(state)];
+    return names[ToSvcMemoryState(state)];
 }
 
 bool VirtualMemoryArea::CanBeMergedWith(const VirtualMemoryArea& next) const {