Add open device packet.

DiscImageChef.Devices/Remote/Enums.cs

@@ -5,6 +5,7 @@ namespace DiscImageChef.Devices.Remote
         Nop = -1,
         Hello = 1,
         CommandListDevices = 2,
-        ResponseListDevices = 3
+        ResponseListDevices = 3,
+        CommandOpen = 4
     }
 }

DiscImageChef.Devices/Remote/Structs.cs

@@ -68,4 +68,13 @@ namespace DiscImageChef.Devices.Remote
 
         public int errno;
     }
+
+    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi, Pack = 1)]
+    public struct DicPacketCommandOpenDevice
+    {
+        public DicPacketHeader hdr;
+
+        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 1024)]
+        public string device_path;
+    }
 }