Use portage machinery instead of package makefiles to install fonts
This does fc-cache, unlike before
https://bugs.gentoo.org/835793
--- a/Makefile.am
+++ b/Makefile.am
@@ -22,9 +22,7 @@
 
 install-exec-hook:
 	chown root:utmp $(DESTDIR)$(bindir)/jfbterm
-	chmod ug+s $(DESTDIR)$(bindir)/jfbterm
 
 install-data-local:
 	$(INSTALL_DATA) $(srcdir)/$(JFBTERM_CONFIG_FILE) $(DESTDIR)$(sysconfdir)/$(JFBTERM_CONFIG_FILE)
-	$(INSTALL_DATA) $(srcdir)/fonts/*.pcf.gz $(DESTDIR)$(datadir)/fonts/jfbterm