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/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceAttribute.h

@@ -6,9 +6,9 @@
 
 #pragma once
 
+#include <Kernel/Devices/GPU/DisplayConnector.h>
 #include <Kernel/FileSystem/SysFS/Component.h>
 #include <Kernel/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceDirectory.h>
-#include <Kernel/Graphics/DisplayConnector.h>
 #include <Kernel/Library/KBuffer.h>
 
 namespace Kernel {

Kernel/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceDirectory.cpp

@@ -6,9 +6,9 @@
 
 #include <Kernel/Bus/PCI/API.h>
 #include <Kernel/Bus/PCI/Access.h>
+#include <Kernel/Devices/GPU/DisplayConnector.h>
 #include <Kernel/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceAttribute.h>
 #include <Kernel/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceDirectory.h>
-#include <Kernel/Graphics/DisplayConnector.h>
 #include <Kernel/Sections.h>
 
 namespace Kernel {

Kernel/FileSystem/SysFS/Subsystems/Devices/Graphics/DisplayConnector/DeviceDirectory.h

@@ -6,8 +6,8 @@
 
 #pragma once
 
+#include <Kernel/Devices/GPU/DisplayConnector.h>
 #include <Kernel/FileSystem/SysFS/Component.h>
-#include <Kernel/Graphics/DisplayConnector.h>
 #include <Kernel/Library/KString.h>
 
 namespace Kernel {