yang: Install ietf-system YANG module

velia now implements ietf-system YANG module [1]. Therefore we have to
install it in our devices too.

[1] https://tools.ietf.org/html/rfc7317

Change-Id: I4c830315bf75fa347111e2b1b1ddd8fe68b9de9e
Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/velia/+/3379
Depends-on: https://cesnet-gerrit-public/c/CzechLight/velia/+/3379
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/velia/+/3379
diff --git a/package/cla-sysrepo/czechlight-install-yang.sh b/package/cla-sysrepo/czechlight-install-yang.sh
index 46191db..0cd93f3 100755
--- a/package/cla-sysrepo/czechlight-install-yang.sh
+++ b/package/cla-sysrepo/czechlight-install-yang.sh
@@ -90,6 +90,11 @@
     sysrepocfg --datastore=startup --format=json --module=czechlight-calibration-device --import="${YANG_DIR}/${CZECHLIGHT}.json"
 fi
 
+if [[ ! -f ${REPO}/ietf-system@2014-08-06.yang ]]; then
+	sysrepoctl --search-dirs /usr/share/velia/yang --install /usr/share/velia/yang/ietf-system@2014-08-06.yang
+    sysrepoctl --change ietf-system --permissions 0664 --apply
+fi
+
 if [[ ! -f ${REPO}/czechlight-lldp@2020-11-04.yang ]]; then
     if compgen -G "${REPO}/czechlight-lldp@*.yang" >/dev/null; then
         sysrepoctl --search-dirs /usr/share/lldp-systemd-networkd-sysrepo/yang --update /usr/share/lldp-systemd-networkd-sysrepo/yang/czechlight-lldp@2020-11-04.yang