None of the contrib programs get installed, so don't build them.

Index: Makefile.in
--- Makefile.in.orig
+++ Makefile.in
@@ -454,7 +454,7 @@ top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
 @ENABLE_GATTRIB_TRUE@GATTRIB_DIR = gattrib
 SUBDIRS = libgeda libgedacairo gaf gschem ${GATTRIB_DIR} \
-	gsymcheck gnetlist-legacy utils symbols docs examples contrib xorn
+	gsymcheck gnetlist-legacy utils symbols docs examples xorn
 
 ACLOCAL_AMFLAGS = -I m4
 
