[SERVICES] Fix booting with DPH enabled

RegSetValueExW tries to read one extra character after the buffer,
to see if a REG_SZ is null terminated

base/system/services/controlset.c

@@ -174,9 +174,10 @@ ScmCopyTree(
             return ERROR_NOT_ENOUGH_MEMORY;
         }
 
+        /* RegSetValueExW tries to read behind the maximum length, so give it space for that */
         lpDataBuffer = HeapAlloc(GetProcessHeap(),
-                                 0,
-                                 dwMaxValueLength);
+                                 HEAP_ZERO_MEMORY,
+                                 dwMaxValueLength + sizeof(WCHAR));
         if (lpDataBuffer == NULL)
         {
             DPRINT1("Buffer allocation failed\n");