USB: Store device descriptor on enumeration

We now store the device descriptor obtained from the device
during enumeration in the device's object in memory instead
of exposing all of the different members contained within it.

Kernel/Devices/USB/USBDevice.cpp

@@ -94,6 +94,7 @@ KResult Device::enumerate()
  VERIFY(transfer_length > 0);
  m_address = s_next_usb_address++;
 
+ memcpy(&m_device_descriptor, &dev_descriptor, sizeof(USBDeviceDescriptor));
  return KSuccess;
 }
 

Kernel/Devices/USB/USBDevice.h

@@ -42,7 +42,8 @@ class Device : public RefCounted<Device> {
 
  u8 address() const { return m_address; }
 
-private:
+ const USBDeviceDescriptor& device_descriptor() const { return m_device_descriptor; }
+
 private:
  PortNumber m_device_port; // What port is this device attached to
  DeviceSpeed m_device_speed; // What speed is this device running at