util, refactor: Improve headers for bitcoin-wallet tool

src/wallet/wallettool.cpp

@@ -2,6 +2,12 @@
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
+#if defined(HAVE_CONFIG_H)
+#include <config/bitcoin-config.h>
+#endif
+
+#include <wallet/wallettool.h>
+
 #include <fs.h>
 #include <util/system.h>
 #include <util/translation.h>