Initial Open5GS support

Change-Id: Iff8b88dc22d8f156572839abb48b0c1377c55e33
diff --git a/src/osmo_gsm_tester/templates/open5gs-hssd.yaml.tmpl b/src/osmo_gsm_tester/templates/open5gs-hssd.yaml.tmpl
new file mode 100644
index 0000000..830e8cd
--- /dev/null
+++ b/src/osmo_gsm_tester/templates/open5gs-hssd.yaml.tmpl
@@ -0,0 +1,85 @@
+db_uri: ${epc.db_uri}
+
+#
+# logger:
+#
+#  o Set OGS_LOG_INFO to all domain level
+#   - If `level` is omitted, the default level is OGS_LOG_INFO)
+#   - If `domain` is omitted, the all domain level is set from 'level'
+#    (Nothing is needed)
+#
+#  o Set OGS_LOG_ERROR to all domain level
+#   - `level` can be set with none, fatal, error, warn, info, debug, trace
+#    level: error
+#
+#  o Set OGS_LOG_DEBUG to mme/emm domain level
+#    level: debug
+#    domain: mme,emm
+#
+#  o Set OGS_LOG_TRACE to all domain level
+#    level: trace
+#    domain: core,fd,hss,event,mem,sock
+#
+logger:
+    file: ${hss.log_filename}
+    level: debug
+
+hss:
+    freeDiameter: ${hss.diameter_filename}
+
+#
+# parameter:
+#
+#  o Number of output streams per SCTP associations.
+#      sctp_streams: 30
+#
+#  o Disable use of IPv4 addresses (only IPv6)
+#      no_ipv4: true
+#
+#  o Disable use of IPv6 addresses (only IPv4)
+#      no_ipv6: true
+#
+#  o Prefer IPv4 instead of IPv6 for estabishing new GTP connections.
+#      prefer_ipv4: true
+#
+#  o Enable Multicast traffic to the UE
+#      multicast: true
+#
+#  o Disable Stateless Address Autoconfiguration for IPv6
+#      no_slaac: true
+#
+parameter:
+
+#
+# max:
+#
+# o Maximum Number of UE per AMF/MME
+#    ue: 1024
+# o Maximum Number of gNB/eNB per AMF/MME
+#    gnb: 32
+#
+max:
+
+#
+# pool:
+#
+# o The default memory pool size was set assuming 1024 UEs.
+#   To connect more UEs, you need to increase the size further.
+#
+#   - Pool-size 128         => 65536 Number
+#   - Pool-size 256         => 16384 Number
+#   - Pool-size 512         => 4096 Number
+#   - Pool-size 1024        => 1024 Number
+#   - Pool-size 2048        => 512 Number
+#   - Pool-size 8192        => 128 Number
+#   - Pool-size 1024*1024   => 8 Number
+#
+#    128:  65536
+#    256:  16384
+#    512:  4096
+#    1024: 1024
+#    2048: 512
+#    8192: 128
+#    big:  8
+#
+pool: