Kernel: Rewrite whole device structure

We now have DevFileSystem which is derived from RamFileSystem. All
devices are RamInodes. We don't have separate DeviceManager anymore.
To iterate over devices, you can loop througn every inode in devfs.

kernel/kernel/PCI.cpp

@@ -1,5 +1,6 @@
 #include <kernel/IO.h>
 #include <kernel/PCI.h>
+#include <kernel/Storage/ATAController.h>
 
 #define INVALID 0xFFFF
 #define MULTI_FUNCTION 0x80
@@ -18,6 +19,7 @@ namespace Kernel
 		s_instance = new PCI();
 		ASSERT(s_instance);
 		s_instance->check_all_buses();
+		s_instance->initialize_devices();
 	}
 
 	PCI& PCI::get()
@@ -91,6 +93,32 @@ namespace Kernel
 		}
 	}
 
+	void PCI::initialize_devices()
+	{
+		for (const auto& pci_device : PCI::get().devices())
+		{
+			switch (pci_device.class_code())
+			{
+				case 0x01:
+				{
+					switch (pci_device.subclass())
+					{
+						case 0x01:
+							if (auto res = ATAController::create(pci_device); res.is_error())
+								dprintln("{}", res.error());
+							break;
+						default:
+							dprintln("unsupported storage device (pci {2H}.{2H}.{2H})", pci_device.class_code(), pci_device.subclass(), pci_device.prog_if());
+							break;
+					}
+					break;
+				}
+				default:
+					break;
+			}
+		}
+	}
+
 	PCIDevice::PCIDevice(uint8_t bus, uint8_t dev, uint8_t func)
 		: m_bus(bus), m_dev(dev), m_func(func)
 	{