ip: Use .api declared error counters

Type: improvement

Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: I822ead1495edb96ee62e53dc5920aa6c565e3621
diff --git a/test/test_gre.py b/test/test_gre.py
index a79819e..cfba559 100644
--- a/test/test_gre.py
+++ b/test/test_gre.py
@@ -58,7 +58,7 @@
         self.pg0.add_stream(pkt)
         self.pg_start()
         # no tunnel created, gre-input not registered
-        err = self.statistics.get_counter("/err/ip4-local/unknown ip protocol")[0]
+        err = self.statistics.get_counter("/err/ip4-local/unknown_protocol")[0]
         self.assertEqual(err, 1)
         err_count = err
 
@@ -69,7 +69,7 @@
         self.pg0.add_stream(pkt)
         self.pg_start()
         # tunnel created, gre-input registered
-        err = self.statistics.get_counter("/err/ip4-local/unknown ip protocol")[0]
+        err = self.statistics.get_counter("/err/ip4-local/unknown_protocol")[0]
         # expect no new errors
         self.assertEqual(err, err_count)