system_information: Set BSS_PAGING_COORDINATION in SI13 for osmo-bts

osmo-bts (in combination with osmo-pcu) has been supporting paging
for CS services via PCU/PACCH for a very long time.  Let's make sure
this is reflected by the correct BSS_PAGING_COORDINATION bit.

Change-Id: I0e80ca5afc06737273b6699bde6e325e454b57f6
Requires: libosmocore.git Ifb2e83eaf05dd36e5b203ed2de1a74864b039e38
Related: OS#2406
diff --git a/src/osmo-bsc/bts_sysmobts.c b/src/osmo-bsc/bts_sysmobts.c
index ad12733..6f9dc77 100644
--- a/src/osmo-bsc/bts_sysmobts.c
+++ b/src/osmo-bsc/bts_sysmobts.c
@@ -58,6 +58,7 @@
 
         osmo_bts_set_feature(&model_sysmobts.features, BTS_FEAT_GPRS);
 	osmo_bts_set_feature(&model_sysmobts.features, BTS_FEAT_EGPRS);
+	osmo_bts_set_feature(&model_sysmobts.features, BTS_FEAT_PAGING_COORDINATION);
 
 	return gsm_bts_model_register(&model_sysmobts);
 }
diff --git a/src/osmo-bsc/system_information.c b/src/osmo-bsc/system_information.c
index de01112..4a1118e 100644
--- a/src/osmo-bsc/system_information.c
+++ b/src/osmo-bsc/system_information.c
@@ -1202,6 +1202,11 @@
 	else
 		si13_default.cell_opts.ext_info.use_egprs_p_ch_req = 0;
 
+	if (osmo_bts_has_feature(&bts->features, BTS_FEAT_PAGING_COORDINATION))
+		si13_default.cell_opts.ext_info.bss_paging_coordination = 1;
+	else
+		si13_default.cell_opts.ext_info.bss_paging_coordination = 0;
+
 	ret = rest_octets_si13(si13->rest_octets, &si13_default);
 	if (ret < 0)
 		return ret;