add gsm0808_create_handover_request_ack()

Related: OS#2283 (inter-BSC Handover, BSC side, MT)
Change-Id: I692292a06c7d66004404560dc4ed933ca9107f9b
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 58a5bfe..3b9fbfd 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -162,6 +162,7 @@
 gsm0808_create_reset_ack;
 gsm0808_create_sapi_reject;
 gsm0808_create_handover_required;
+gsm0808_create_handover_request_ack;
 gsm0808_prepend_dtap_header;
 gsm0808_enc_aoip_trasp_addr;
 gsm0808_dec_aoip_trasp_addr;