Always generate bitcoinstrings.cpp on make translate

`bitcoinstrings.cpp` is to be generated at release time. Hence,
it should not depend on whether the source files are younger as the
releaser may proceed from a fresh checkout.

Author: Franck Royer

src/Makefile.qt.include

@@ -353,9 +353,9 @@ QT_QM=$(QT_TS:.ts=.qm)
 
 SECONDARY: $(QT_QM)
 
-$(srcdir)/qt/bitcoinstrings.cpp: $(libbitcoin_server_a_SOURCES) $(libbitcoin_wallet_a_SOURCES) $(libbitcoin_common_a_SOURCES) $(libbitcoin_zmq_a_SOURCES) $(libbitcoin_consensus_a_SOURCES) $(libbitcoin_util_a_SOURCES)
+$(srcdir)/qt/bitcoinstrings.cpp: FORCE
 	@test -n $(XGETTEXT) || echo "xgettext is required for updating translations"
-	$(AM_V_GEN) cd $(srcdir); XGETTEXT=$(XGETTEXT) COPYRIGHT_HOLDERS="$(COPYRIGHT_HOLDERS)" $(PYTHON) ../share/qt/extract_strings_qt.py $^
+	$(AM_V_GEN) cd $(srcdir); XGETTEXT=$(XGETTEXT) COPYRIGHT_HOLDERS="$(COPYRIGHT_HOLDERS)" $(PYTHON) ../share/qt/extract_strings_qt.py $(libbitcoin_server_a_SOURCES) $(libbitcoin_wallet_a_SOURCES) $(libbitcoin_common_a_SOURCES) $(libbitcoin_zmq_a_SOURCES) $(libbitcoin_consensus_a_SOURCES) $(libbitcoin_util_a_SOURCES)
 
 translate: $(srcdir)/qt/bitcoinstrings.cpp $(QT_FORMS_UI) $(QT_FORMS_UI) $(BITCOIN_QT_BASE_CPP) qt/bitcoin.cpp $(BITCOIN_QT_WINDOWS_CPP) $(BITCOIN_QT_WALLET_CPP) $(BITCOIN_QT_H) $(BITCOIN_MM)
 	@test -n $(LUPDATE) || echo "lupdate is required for updating translations"