Kernel/IPC: Implement StaticBuffer translation for HLE services that use the HLERequestContext architecture.

The real kernel requires services to set up their static buffer targets ahead of time. This implementation does not require that and will simply create the storage for the buffers as they are processed in the incoming IPC request.

Static buffers are kept in an unordered_map keyed by their buffer id, and are written into the already-setup area of the request thread when responding an IPC request.

This fixes a regression (crash) introduced in #2992.

This PR introduces more warnings due to the [[deprecated]] attribute being added to void PushStaticBuffer(VAddr buffer_vaddr, size_t size, u8 buffer_id); and VAddr PopStaticBuffer(size_t* data_size);

src/core/hle/kernel/hle_ipc.h

@@ -119,6 +119,18 @@ public:
      */
     void ClearIncomingObjects();
 
+    /**
+     * Retrieves the static buffer identified by the input buffer_id. The static buffer *must* have
+     * been created in PopulateFromIncomingCommandBuffer by way of an input StaticBuffer descriptor.
+     */
+    const std::vector<u8>& GetStaticBuffer(u8 buffer_id) const;
+
+    /**
+     * Sets up a static buffer that will be copied to the target process when the request is
+     * translated.
+     */
+    void AddStaticBuffer(u8 buffer_id, std::vector<u8> data);
+
     /// Populates this context with data from the requesting process/thread.
     ResultCode PopulateFromIncomingCommandBuffer(const u32_le* src_cmdbuf, Process& src_process,
                                                  HandleTable& src_table);
@@ -131,6 +143,8 @@ private:
     SharedPtr<ServerSession> session;
     // TODO(yuriks): Check common usage of this and optimize size accordingly
     boost::container::small_vector<SharedPtr<Object>, 8> request_handles;
+    // The static buffers will be created when the IPC request is translated.
+    std::array<std::vector<u8>, IPC::MAX_STATIC_BUFFERS> static_buffers;
 };
 
 } // namespace Kernel