[otbn] Add testplan entry for lifecycle escalations

Signed-off-by: Philipp Wagner <phw@lowrisc.org>

hw/ip/otbn/data/otbn_testplan.hjson

diff --git a/hw/ip/otbn/data/otbn_testplan.hjson b/hw/ip/otbn/data/otbn_testplan.hjson
index e4c69b8..ede7e61 100644
--- a/hw/ip/otbn/data/otbn_testplan.hjson
+++ b/hw/ip/otbn/data/otbn_testplan.hjson
@@ -87,5 +87,13 @@
       milestone: V2
       tests: []
     }
+    {
+      name: lc_escalation
+      desc: '''
+            Trigger the life cycle escalation input.
+            '''
+      milestone: V2
+      tests: []
+    }
   ]
 }