Add missing Device.h include into GParted_Core and Win_GParted

The files GParted_Core.h, GParted_Core.cc and Win_GParted.cc all use the
Device type but don't include Device.h for it's definition.  Include it.

include/GParted_Core.h

@@ -19,6 +19,7 @@
 #define GPARTED_GPARTED_CORE_H
 
 #include "BlockSpecial.h"
+#include "Device.h"
 #include "FileSystem.h"
 #include "Operation.h"
 #include "Partition.h"

src/GParted_Core.cc

@@ -18,6 +18,7 @@
 #include "GParted_Core.h"
 #include "CopyBlocks.h"
 #include "BlockSpecial.h"
+#include "Device.h"
 #include "DMRaid.h"
 #include "FileSystem.h"
 #include "FS_Info.h"

src/Win_GParted.cc

@@ -16,6 +16,7 @@
  */
 
 #include "Win_GParted.h"
+#include "Device.h"
 #include "Dialog_Progress.h"
 #include "DialogFeatures.h"
 #include "DialogPasswordEntry.h"