message: [Build] Fix typo in Qt test makefile
  Typo in target flags name causes the position independent flag (-fPIC or
  fPIE) to not be properly passed on when linking the Qt test binary.
  On systems that have Qt built with reduced exports, this causes a linker
  error.
  Gitian and depends based builds aren't affected.
diff: @@ -41,7 +41,7 @@ qt_test_test_pivx_qt_LDADD += $(LIBBITCOIN_CLI) $(LIBBITCOIN_COMMON) $(LIBBITCOI
  $(QR_LIBS) $(PROTOBUF_LIBS) $(BDB_LIBS) $(SSL_LIBS) $(CRYPTO_LIBS) $(MINIUPNPC_LIBS) $(LIBSECP256K1) \
  $(EVENT_PTHREADS_LIBS) $(EVENT_LIBS)
  qt_test_test_pivx_qt_LDFLAGS = $(RELDFLAGS) $(AM_LDFLAGS) $(QT_LDFLAGS) $(LIBTOOL_APP_LDFLAGS)
  -qt_test_test_bitcoin_qt_CXXFLAGS = $(AM_CXXFLAGS) $(QT_PIE_FLAGS)
  +qt_test_test_pivx_qt_CXXFLAGS = $(AM_CXXFLAGS) $(QT_PIE_FLAGS)
  CLEAN_BITCOIN_QT_TEST = $(TEST_QT_MOC_CPP) qt/test/*.gcda qt/test/*.gcno
  