IuPS: add GMM Service Request related constants and value_str

Change-Id: Ie023fc78099932f95cc8f1b3a04fe25dfd14bc35
diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index f530b6f..dc8559f 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -56,6 +56,7 @@
 gprs_upd_t_strs;
 gprs_det_t_mo_strs;
 gprs_det_t_mt_strs;
+gprs_service_t_strs;
 
 gsm0341_build_msg;