Fix shared-library symlink to be relative (and local), rather than
absolute.

	-mi

--- Makefile.in	2014-10-28 05:39:12.000000000 -0400
+++ Makefile.in	2015-04-09 19:41:53.000000000 -0400
@@ -366,8 +366,8 @@
 	$(INSTALL) $(libpure) $(DESTDIR)$(libdir)/$(libpure)
 ifneq ($(libpure), $(libpure_soname))
-	ln -sf $(libdir)/$(libpure) $(DESTDIR)$(libdir)/$(libpure_soname)
+	ln -sf $(libpure) $(DESTDIR)$(libdir)/$(libpure_soname)
 endif
 ifneq ($(libpure), $(libpure_lnkname))
-	ln -sf $(libdir)/$(libpure) $(DESTDIR)$(libdir)/$(libpure_lnkname)
+	ln -sf $(libpure) $(DESTDIR)$(libdir)/$(libpure_lnkname)
 endif
 endif