Initial srsLTE support

2 tests (iperf3, ping) working against a full srs{UE,ENB,EPC} network
using ZeroMQ backend for RF (so no real RF support yet, that will come
next).

Related: OS##4295, OS#4296

Change-Id: I290c0d79258a9f94f00c7ff2e1c6c5579c0e32f4
diff --git a/src/osmo_gsm_tester/templates/srsenb_drb.conf.tmpl b/src/osmo_gsm_tester/templates/srsenb_drb.conf.tmpl
new file mode 100644
index 0000000..32b6e93
--- /dev/null
+++ b/src/osmo_gsm_tester/templates/srsenb_drb.conf.tmpl
@@ -0,0 +1,54 @@
+
+// All times are in ms. Use -1 for infinity, where available
+
+qci_config = (
+
+{
+  qci=7;
+  pdcp_config = {
+    discard_timer = 100;                
+    pdcp_sn_size = 12;                  
+  }
+  rlc_config = {
+    ul_um = {
+      sn_field_length = 10; 
+    };
+    dl_um = {
+      sn_field_length = 10; 
+      t_reordering    = 45;             
+    };
+  };
+  logical_channel_config = {
+    priority = 13; 
+    prioritized_bit_rate   = -1; 
+    bucket_size_duration  = 100; 
+    log_chan_group = 2; 
+  };
+},
+{
+  qci=9;
+  pdcp_config = {
+    discard_timer = -1;
+    status_report_required = true;
+  }
+  rlc_config = {
+    ul_am = {
+      t_poll_retx = 120;
+      poll_pdu = 64;
+      poll_byte = 750;
+      max_retx_thresh = 16;
+    };
+    dl_am = {
+      t_reordering = 50;
+      t_status_prohibit = 50;
+    };
+  };
+  logical_channel_config = {
+    priority = 11; 
+    prioritized_bit_rate   = -1; 
+    bucket_size_duration  = 100; 
+    log_chan_group = 3; 
+  };
+}
+
+);