kernel/error: Add error code for the handle table being full

This replaces the lingering 3DS constant with the proper one, and
utilizes it within HandleTable's Create() member function.

src/core/hle/kernel/handle_table.cpp

@@ -26,7 +26,7 @@ ResultVal<Handle> HandleTable::Create(SharedPtr<Object> obj) {
     u16 slot = next_free_slot;
     if (slot >= generations.size()) {
         LOG_ERROR(Kernel, "Unable to allocate Handle, too many slots in use.");
-        return ERR_OUT_OF_HANDLES;
+        return ERR_HANDLE_TABLE_FULL;
     }
     next_free_slot = generations[slot];