Send RADIO LINK TIMEOUT value via OML attribute to BTS

The same radio link timeout value is used for BTS and MS side.
diff --git a/openbsc/src/libbsc/bts_ipaccess_nanobts.c b/openbsc/src/libbsc/bts_ipaccess_nanobts.c
index 9e1b3c2..dfb5a45 100644
--- a/openbsc/src/libbsc/bts_ipaccess_nanobts.c
+++ b/openbsc/src/libbsc/bts_ipaccess_nanobts.c
@@ -231,6 +231,10 @@
 	/* patch CGI */
 	abis_nm_ipaccess_cgi(nanobts_attr_bts+sizeof(nanobts_attr_bts)-7, bts);
 
+	/* patch CON_FAIL_CRIT */
+	nanobts_attr_bts[13] =
+		get_radio_link_timeout(&bts->si_common.cell_options);
+
 	/* patch the power reduction */
 	nanobts_attr_radio[1] = bts->c0->max_power_red / 2;