om2000: added support for ericssons sabm negotiation

This patch adds support for ericssons sambm negotiation.

This patch depends on libosmo-abis commit:
2788c7eacab91cd39d68e316fc8ee87763bbfeb4

Change-Id: I56b1c1cef07a61143fc0e8058480805cddfeff96
diff --git a/openbsc/src/libbsc/bts_ericsson_rbs2000.c b/openbsc/src/libbsc/bts_ericsson_rbs2000.c
index 1d122ec..1300b4a 100644
--- a/openbsc/src/libbsc/bts_ericsson_rbs2000.c
+++ b/openbsc/src/libbsc/bts_ericsson_rbs2000.c
@@ -71,6 +71,9 @@
 			continue;
 
 		llist_for_each_entry(link, &ts->sign.sign_links, list) {
+			lapd_instance_set_profile(ts->lapd,
+						  &lapd_profile_abis_ericsson);
+
 			if (start)
 				lapd_sap_start(ts->lapd, link->tei, link->sapi);
 			else