{enb,epc,ms}_srs: remove uneeded class variable

self.kpis is define in base class

Change-Id: I49c9c9cdf7bc31270d3cfe182a79b197a742dd2c
diff --git a/src/osmo_gsm_tester/obj/enb_srs.py b/src/osmo_gsm_tester/obj/enb_srs.py
index 9d7eca3..77f196f 100644
--- a/src/osmo_gsm_tester/obj/enb_srs.py
+++ b/src/osmo_gsm_tester/obj/enb_srs.py
@@ -74,7 +74,6 @@
         self.metrics_file = None
         self.stop_sleep_time = 6 # We require at most 5s to stop
         self.testenv = testenv
-        self.kpis = None
         self._additional_args = []
         if not rf_type_valid(conf.get('rf_dev_type', None)):
             raise log.Error('Invalid rf_dev_type=%s' % conf.get('rf_dev_type', None))
diff --git a/src/osmo_gsm_tester/obj/epc_srs.py b/src/osmo_gsm_tester/obj/epc_srs.py
index dae8a56..80f66e8 100644
--- a/src/osmo_gsm_tester/obj/epc_srs.py
+++ b/src/osmo_gsm_tester/obj/epc_srs.py
@@ -57,7 +57,6 @@
         self.remote_log_file = None
         self.remote_pcap_file = None
         self.enable_pcap = False
-        self.kpis = None
         self.subscriber_list = []
 
     def cleanup(self):
diff --git a/src/osmo_gsm_tester/obj/ms_srs.py b/src/osmo_gsm_tester/obj/ms_srs.py
index be3e799..084edcb 100644
--- a/src/osmo_gsm_tester/obj/ms_srs.py
+++ b/src/osmo_gsm_tester/obj/ms_srs.py
@@ -96,7 +96,6 @@
         self.remote_metrics_file = None
         self.enable_pcap = False
         self.num_carriers = 1
-        self.kpis = None
         self.testenv = testenv
         self._additional_args = []
         if not rf_type_valid(conf.get('rf_dev_type', None)):