patch 8.0.0694: building in shadow directory does not work

Problem:    Building in shadow directory does not work.  Running Vim fails.
Solution:   Add the new libvterm directory.  Add missing change in command
            list.
diff --git a/src/Makefile b/src/Makefile
index 907fdb1..49a8ef4 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -2810,7 +2810,7 @@
 
 shadow:	runtime pixmaps
 	$(MKDIR_P) $(SHADOWDIR)
-	cd $(SHADOWDIR); ln -s ../*.[chm] ../*.in ../*.sh ../*.xs ../*.xbm ../gui_gtk_res.xml ../toolcheck ../proto ../vimtutor ../gvimtutor ../install-sh .
+	cd $(SHADOWDIR); ln -s ../*.[chm] ../*.in ../*.sh ../*.xs ../*.xbm ../gui_gtk_res.xml ../toolcheck ../proto ../libvterm ../vimtutor ../gvimtutor ../install-sh .
 	mkdir $(SHADOWDIR)/auto
 	cd $(SHADOWDIR)/auto; ln -s ../../auto/configure .
 	$(MKDIR_P) $(SHADOWDIR)/po