Fix --disable-wallet build after merge of #5681

Author: laanwj

src/init.cpp

@@ -23,6 +23,7 @@
 #include "ui_interface.h"
 #include "util.h"
 #include "utilmoneystr.h"
+#include "validationinterface.h"
 #ifdef ENABLE_WALLET
 #include "wallet/wallet.h"
 #include "wallet/walletdb.h"

src/rpcmining.cpp

@@ -13,6 +13,7 @@
 #include "pow.h"
 #include "rpcserver.h"
 #include "util.h"
+#include "validationinterface.h"
 #ifdef ENABLE_WALLET
 #include "wallet/db.h"
 #include "wallet/wallet.h"