Kernel: Move all Graphics-related code into Devices/GPU directory

Like the HID, Audio and Storage subsystem, the Graphics subsystem (which
handles GPUs technically) exposes unix device files (typically in /dev).
To ensure consistency across the repository, move all related files to a
new directory under Kernel/Devices called "GPU".

Also remove the redundant "GPU" word from the VirtIO driver directory,
and the word "Graphics" from GraphicsManagement.{h,cpp} filenames.

Kernel/Devices/GPU/Console/ContiguousFramebufferConsole.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2021, Sahan Fernando <sahan.h.fernando@gmail.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <Kernel/Devices/GPU/Console/GenericFramebufferConsole.h>
+
+namespace Kernel::Graphics {
+
+class ContiguousFramebufferConsole final : public GenericFramebufferConsole {
+public:
+    static NonnullLockRefPtr<ContiguousFramebufferConsole> initialize(PhysicalAddress, size_t width, size_t height, size_t pitch);
+
+    virtual void set_resolution(size_t width, size_t height, size_t pitch) override;
+    virtual void flush(size_t, size_t, size_t, size_t) override { }
+
+private:
+    virtual u8* framebuffer_data() override
+    {
+        return m_framebuffer_region->vaddr().as_ptr();
+    }
+    OwnPtr<Memory::Region> m_framebuffer_region;
+    ContiguousFramebufferConsole(PhysicalAddress, size_t width, size_t height, size_t pitch);
+    PhysicalAddress m_framebuffer_address;
+};
+
+}