add j4 to wsjtx build

functions/additional.function

@@ -178,7 +178,7 @@ WSJTX() {
 	cd $FT8DIR
 	cmake -D CMAKE_INSTALL_PREFIX=${BUILDDIR}/$FT8DIR
 	cmake -DWSJT_SKIP_MANPAGES=ON -DWSJT_GENERATE_DOCS=OFF
-	sudo cmake --build . --target install
+	sudo cmake --build . --target install -j4
 	sudo mv ${BUILDDIR}/${FT8DIR}/bin/* /usr/local/bin/
 	sudo cp ${BUILDDIR}/${FT8DIR}/share/applications/wsjtx.desktop /usr/share/applications/
 	sudo cp ${BUILDDIR}/${FT8DIR}/share/pixmaps/wsjtx_icon.png /usr/share/pixmaps/