Fix make install on macOS
https://github.com/hoytech/vmtouch/commit/75f04153601e552ef52f5e3d349eccd7e6670303
--- Makefile.orig
+++ Makefile
@@ -16,8 +16,9 @@ vmtouch.8: vmtouch.pod
 	pod2man --section 8 --center "System Manager's Manual" --release " " vmtouch.pod > vmtouch.8
 
 install: vmtouch vmtouch.8
-	install -Dm 0755 vmtouch $(DESTDIR)$(BINDIR)/vmtouch
-	install -Dm 0644 vmtouch.8 $(DESTDIR)$(MANDIR)/vmtouch.8
+	mkdir -p $(DESTDIR)$(BINDIR) $(DESTDIR)$(MANDIR)
+	install -m 0755 vmtouch $(DESTDIR)$(BINDIR)/vmtouch
+	install -m 0644 vmtouch.8 $(DESTDIR)$(MANDIR)/vmtouch.8
 
 clean:
 	rm -f vmtouch vmtouch.8