Added needed string.h includes.

dlls/comctl32/comboex.c

@@ -63,6 +63,7 @@
  *
  */
 
+#include <string.h>
 #include "winbase.h"
 #include "commctrl.h"
 #include "debugtools.h"

dlls/shlwapi/reg.c

@@ -2,6 +2,7 @@
  * SHLWAPI registry functions
  */
 
+#include <string.h>
 #include "windef.h"
 #include "winbase.h"
 #include "wingdi.h"

dlls/x11drv/x11ddraw.c

@@ -4,6 +4,7 @@
  * Copyright 2001 TransGaming Technologies, Inc.
  */
 
+#include <string.h>
 #include "ts_xlib.h"
 #include "x11drv.h"
 #include "x11ddraw.h"

dlls/x11drv/xvidmode.c

@@ -5,6 +5,7 @@
  */
 
 #include "config.h"
+#include <string.h>
 
 /* FIXME: ChangeDisplaySettings ought to be able to use this */