libdpkg: Add missing symbols to the version script

lib/dpkg/libdpkg.map

@@ -192,6 +192,9 @@ LIBDPKG_PRIVATE {
 	copy_dependency_links;
 	pkg_sorter_by_name;
 	pkg_summary;
+	pkg_abbrev_want;
+	pkg_abbrev_status;
+	pkg_abbrev_eflag;
 
 	# Package list handling
 	pkg_list_new;